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#81
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Harsh, "aliased" sound with digital TV converter box.
The last YIQ wncoder I saw was in an RCA TK45 color camera from
around '75. All I've seen since then are equiband Y, R-Y, B-Y encoders where the modulation axes are on the 0 and 90 degree axes rather than rotated 33 degrees. That bandwidth filtering hasn'r been done that way in a long time. S- video _could_ have more bandwidth if a custom encoder was built but in fact they are simply an encoder where the modulated subcarrier and luminance (Y) are not summed together and are instead sent out separately on their own cables. Why would anyone bother to make a "super" S-video encoder since the destination is a limited response (sompared to a broadcast VTR) VHS deck? I can see generating and recording R-Y and B-Y signals, as it makes it easier to convert the signal to PAL and SECAM. But you can't transmit _equal-bandwidth_ NTSC signals, as that would push the bandwidth beyond 5MHz. At some point NTSC color has to be converted to IQ. OK, you guys talk about "500 lines" resolution on a Betamax or an S-VHS but those numbers are pure BS. I don't remember any of us talking aobut such things. My memory is that Betamax originally had 240 lines, which equates to about 3MHz, the minimum bandwidth needed for an "acceptably" sharp picture on a 20" screen. 500 lines of resolution on American TV would require more than 6MHz of luminance bandwidth, an impossibility for Beta or VHS. |
#82
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
William Sommerwerck wrote:
Since the s-video output and the composite output are both NTSC, it is impossible for either the s-video output or the composite output to have *more* output than the NTSC output -- they *ARE* NTSC outputs. This might be true in practice, but "it ain't necessarily so". How would they not be NTSC? --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#83
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"William Sommerwerck" wrote in
message Yes, it's brilliant. (It's one of the great 20th century inventions.) But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth If we extrapolate this discussion to audio, then we have Willaim Sommerwerck, MP3 advocate! ;-) has little to do with the eye's (relatively) limited color resolution and The eye's limited color and intensity resolution is at least an effect that is at least perceivable. We have to distinguish between sensory limits like those due to rods and cones in the eye, and perceptual limits due to the brain's data crunching bottlenecks and limited training. a great deal to do with what I said -- most objects are colored with constant saturation, This is like saying that all objects are each well-modeled as being painted all over with the same paint, with such variations in coloration that exist being related to things like the location of light sources. which greatly reduces the required bandwidth for the chrominance signals -- or more precisely, lets them convey more useful information. The "same paint" model works well for a lot of artificial objects, some natural objects, and many more natural objects if viewed from a distance. But it doesn't work for everything. Many objects, both artificial and natural, don't follow the "same paint" rule. I contemplate the evolution of special effects in movies. In their day, I found the special effects in the better early-1950s science fiction movies to be compelling. Today, my brain is trained by experience to see through many of them, and I perceive them as being hopelessly toy-like. I can do a binary search of sorts and contemplate the special effects in the hottest movies of the early 80s. While the better movies of those days are not so toy-like, they are also not nearly as compelling as the latest-greatest. |
#84
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"Scott Dorsey" wrote in message
William Sommerwerck wrote: Since the s-video output and the composite output are both NTSC, Only if the source is NTSC. Today we have many common video sources that exceed NTSC limits in many ways. it is impossible for either the s-video output or the composite output to have *more* output than the NTSC output -- they *ARE* NTSC outputs. This might be true in practice, but "it ain't necessarily so". How would they not be NTSC? Only broadcast video *must* be NTSC, right? |
#85
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
On Feb 28, 8:37*am, "William Sommerwerck"
wrote: But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth has little to do with the eye's (relatively) limited color resolution and a great deal to do with what I said -- most objects are colored with constant saturation, which greatly reduces the required bandwidth for the chrominance signals -- or more precisely, lets them convey more useful information. If it's true that colors are applied with constant saturation, then that would explain why many consider NTSC to provide cartoon-like images. Perhaps what you're really saying is that the eyes are not as sensitive to color intensity variations as they are to luminance variations, in which case it's back to "limited color resolution." Bert |
#86
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"Albert Manfredi" wrote in message
... On Feb 28, 8:37 am, "William Sommerwerck" wrote: and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth has little to do with the eye's (relatively) limited color resolution and a great deal to do with what I said -- most objects are colored with constant saturation, which greatly reduces the required bandwidth for the chrominance signals -- or more precisely, lets them convey more useful information. If it's true that colors are applied with constant saturation, then that would explain why many consider NTSC to provide cartoon-like images. Perhaps what you're really saying is that the eyes are not as sensitive to color intensity variations as they are to luminance variations, in which case it's back to "limited color resolution." I'm saying nothing of the sort. Those who consider NTSC to provide "cartoon-like images" know nothing about color television. PAL and SECAM use color-difference signals as well. When you subtract the luminance signal from the color-primary signals, you get a signal that represents ONLY the saturation of the color -- nothing else. As most colors are of constant saturation, there is less "information" in the color-difference signal -- redundant information that already appears in the luminance -- thus requiring less bandwidth. If you don't understand this, think of a cube illuminated from the side, and what the color-primary image and color-difference image would look like. Then you will understand. |
#87
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"Arny Krueger" wrote in message
... "William Sommerwerck" wrote in message Yes, it's brilliant. (It's one of the great 20th century inventions.) But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth If we extrapolate this discussion to audio, then we have Willaim Sommerwerck, MP3 advocate! ;-) God, no. I hate compressed audio. (Dolby Digital, at least.) has little to do with the eye's (relatively) limited color resolution and The eye's limited color and intensity resolution is at least an effect that is at least perceivable. In the NTSC system, this difference shows up in the bandwidth of the color signals. The researchers determined that (for a 480-line, 30-frame system, on a 21" screen, presumably) you could see full red/green/blue-primaries color only up to 0.5MHz, while only colors that could be synthesized from red-orange and blue-green primaries were visible from 0.5MHz to 1.5MHz. * Above 1.5MHz, the eye saw only B&W. So the 0.5MHz I signal is yellow/purple, and the 1.5MHz Q signal is red-orange/blue-green. But this has _nothing whatever_ to do with what I'm talking about. One of the nice things about NTSC (and PAL for that matter -- they're basically the same system) is that the use of color-difference signals (rather than color-primary signals) removes any redundancy. The color signals contain ZERO information about brightness. Which is good, because the brightness information is already conveyed by the Y signal. It doesn't need to be contained in the color signals. * Note that these are roughly the early two-strip Technicolor primaries. The overall gamut is not very broad, but "Secret of the Wax Museum" is surprisingly good. This is like saying that all objects are each well-modeled as being painted all over with the same paint, with such variations in coloration that exist being related to things like the location of light sources. Not coloration (hue), but lightness (value). Otherwise, that is absolutely correct. The "same paint" model works well for a lot of artificial objects, some natural objects, and many more natural objects if viewed from a distance. Many objects, both artificial and natural, don't follow the "same paint" rule. But it's true for most objects, natural or artificial. If you don't believe this, try to find any colored object -- natural or artificial -- that is _not_ "constant saturation". You're most likely to find it in flowers and fabric patterns. I don't want to argue this too much, because most people don't have a good understanding of color analysis and systhesis. |
#88
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"William Sommerwerck" wrote in
message "Arny Krueger" wrote in message ... "William Sommerwerck" wrote in message Yes, it's brilliant. (It's one of the great 20th century inventions.) But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth If we extrapolate this discussion to audio, then we have Willaim Sommerwerck, MP3 advocate! ;-) God, no. I hate compressed audio. (Dolby Digital, at least.) (1) Dolby Digital is really old-old tech, predating MP3 by lots. (2) Usual grousing about what people say and what they actually hear with their eyes closed. has little to do with the eye's (relatively) limited color resolution and The eye's limited color and intensity resolution is at least an effect that is at least perceivable. In the NTSC system, this difference shows up in the bandwidth of the color signals. The researchers determined that (for a 480-line, 30-frame system, on a 21" screen, presumably) you could see full red/green/blue-primaries color only up to 0.5MHz, Unfortunately, by the end of the NTSC era, 32 and 36 inch sets were mainstream, even average. 42 inch sets were common. NTSC looked like $#@!! on large screens - barely tolerable on 32 inch sets. while only colors that could be synthesized from red-orange and blue-green primaries were visible from 0.5MHz to 1.5MHz. * Above 1.5MHz, the eye saw only B&W. So the 0.5MHz I signal is yellow/purple, and the 1.5MHz Q signal is red-orange/blue-green. This would all be sensory-based, no doubt tested with what amounted to be synthetic, worst-case test patterns. But this has _nothing whatever_ to do with what I'm talking about. Right, you're talking about perception. One of the nice things about NTSC (and PAL for that matter -- they're basically the same system) is that the use of color-difference signals (rather than color-primary signals) removes any redundancy. The color signals contain ZERO information about brightness. Which is good, because the brightness information is already conveyed by the Y signal. It doesn't need to be contained in the color signals. OK. * Note that these are roughly the early two-strip Technicolor primaries. The overall gamut is not very broad, but "Secret of the Wax Museum" is surprisingly good. OK. This is like saying that all objects are each well-modeled as being painted all over with the same paint, with such variations in coloration that exist being related to things like the location of light sources. Not coloration (hue), but lightness (value). Otherwise, that is absolutely correct. Ah yes, I need to reload some long-unused parts of my vocabulary. The "same paint" model works well for a lot of artificial objects, some natural objects, and many more natural objects if viewed from a distance. Many objects, both artificial and natural, don't follow the "same paint" rule. But it's true for most objects, natural or artificial. If you don't believe this, try to find any colored object -- natural or artificial -- that is _not_ "constant saturation". By this you mean constant saturation of a given color hue, no? You're most likely to find it in flowers and fabric patterns. And certain trees and rocks. Water with certain lighting and/or degrees of activity. Artificial objects with exposed frameworks. Artificial objects designed to be highly visible. Much text. I don't want to argue this too much, because most people don't have a good understanding of color analysis and systhesis. One point is that the DVD was one of the larger beginnings of the end for NTSC TV. |
#89
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
Arny Krueger wrote:
"Scott Dorsey" wrote in message William Sommerwerck wrote: Since the s-video output and the composite output are both NTSC, Only if the source is NTSC. Today we have many common video sources that exceed NTSC limits in many ways. it is impossible for either the s-video output or the composite output to have *more* output than the NTSC output -- they *ARE* NTSC outputs. This might be true in practice, but "it ain't necessarily so". How would they not be NTSC? Only broadcast video *must* be NTSC, right? Well, in terms of the fact that the FCC will only come after you if your broadcast waveform doesn't match the NTSC specs, yes. But in fact, just about everything in use today meets the NTSC specs, other than VHS machines which need a time base corrector to meet timing specifications and which are going away very fast. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#90
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"Arny Krueger" wrote in message
... In the NTSC system, this difference shows up in the bandwidth of the color signals. The researchers determined that (for a 480-line, 30-frame system, on a 21" screen, presumably) you could see full red/green/blue-primaries color only up to 0.5MHz, Unfortunately, by the end of the NTSC era, 32 and 36 inch sets were mainstream, even average. 42 inch sets were common. NTSC looked like $#@!! on large screens -- barely tolerable on 32" sets. I remember the early 25" Sony consoles. They had really weak color, though I don't know why. However, I own a 32" Toshiba IDTV and and Sony 36" IDTV. They display spectacularly good NTSC images. Both digitally goose the luminance, and (as far as I know) both have full-bandwidth chroma demodulation. By the way, the original Advent projector had full-bandwidth color. But this has _nothing whatever_ to do with what I'm talking about. Right, you're talking about perception. No, I'm talking objective fact. Color-difference signals require less bandwidth than color-primary signals. Many objects, both artificial and natural, don't follow the "same paint" rule. But it's true for most objects, natural or artificial. If you don't believe this, try to find any colored object -- natural or artificial -- that is _not_ "constant saturation". By this you mean constant saturation of a given color hue, no? Yes. It would be meaningless to talk about different hues. And certain trees and rocks. Water with certain lighting and/or degrees of activity. Artificial objects with exposed frameworks. Artificial objects designed to be highly visible. Much text. Text? Are you referring to illuminated manuscripts? grin One point is that the DVD was one of the larger beginnings of the end for NTSC TV. I don't want to be too quick to defend NTSC, but it can be exceptionally good. It's not that NTSC is of lower quality than DVD, but rather that DVD is better. |
#91
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
Arny Krueger wrote:
"William Sommerwerck" wrote in message "Arny Krueger" wrote in message ... "William Sommerwerck" wrote in message Yes, it's brilliant. (It's one of the great 20th century inventions.) But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth If we extrapolate this discussion to audio, then we have Willaim Sommerwerck, MP3 advocate! ;-) God, no. I hate compressed audio. (Dolby Digital, at least.) (1) Dolby Digital is really old-old tech, predating MP3 by lots. What difference does it make when it was created? |
#92
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
Scott Dorsey wrote:
William Sommerwerck wrote: Since the s-video output and the composite output are both NTSC, it is impossible for either the s-video output or the composite output to have *more* output than the NTSC output -- they *ARE* NTSC outputs. This might be true in practice, but "it ain't necessarily so". How would they not be NTSC? --scott A case for S-Video in preference to Composite: Let's consider the case of cable delivery of a 480i broadcast. The signal originates from the station as a digital feed from the station to the cable company. (In San Diego, Cox maintains fiber feeds from each 'must carry' station.) At this point, the signal it subject to the limitations of the NTSC spec and Cox is receiving something better than the OTA signal. The cable company produces two distinct products: 1) A conventional NTSC analog signal that it delivers to the customer (via format conversions as it travels through the cable infrastructure). This RF signal is delivered directly to the customer's TV receiver or, is demodulated in the STB and presented to the customer as either an R.F. signal, in NTSC format on Channel 3/4; or, a composite video signal -- essentially the baseband version of the NTSC signal; or, an S-Video output of luminance and color. All three of these outputs are limited in quality by the limitations inherent in NTSC. 2) A digital signal applied, along with one or more other signals, to an RF channel compatible with the STB. This signal will have been sufficiently compressed to fit in the allocated bandwidth. This signal is detected and made available to the customer by perhaps four outputs; RF (NTSC), Composite (NTSC-baseband), Component and S--Video. The RF and Composite outputs are subject to the limitations inherent in the NTSC spec. The S-Video and Component outputs may be slightly superior since NTSC wasn't imposed between the originating station and the customer's STB. I've also seen this work in reverse where the cable company heavily compressed the digital feeds for less popular media (to fit three or four signals into a single RF slot). The analog signals (raw NTSC-RF) were superior to the output from the STB. -- pj |
#93
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"trotsky" wrote in message
news:vACxj.1219$TT4.358@attbi_s22 Arny Krueger wrote: "William Sommerwerck" wrote in message "Arny Krueger" wrote in message ... "William Sommerwerck" wrote in message Yes, it's brilliant. (It's one of the great 20th century inventions.) But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth If we extrapolate this discussion to audio, then we have Willaim Sommerwerck, MP3 advocate! ;-) God, no. I hate compressed audio. (Dolby Digital, at least.) (1) Dolby Digital is really old-old tech, predating MP3 by lots. What difference does it make when it was created? Perceptual coding was and is a work in progress. Progress was pretty rapid at the time that DD was introduced and the decade following it. Dolby AC-3 AKA Dolby Digital was introduced in 1991. It is a proprietary standard, and has not changed a lot over the years. MP3 has remained a work in progress since 1989. The rate at which MP3 coders were improved slowed down quite a bit after ca. 1998, but improvement may still be possible. |
#94
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
Arny Krueger wrote:
"trotsky" wrote in message news:vACxj.1219$TT4.358@attbi_s22 Arny Krueger wrote: "William Sommerwerck" wrote in message "Arny Krueger" wrote in message ... "William Sommerwerck" wrote in message Yes, it's brilliant. (It's one of the great 20th century inventions.) But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth If we extrapolate this discussion to audio, then we have Willaim Sommerwerck, MP3 advocate! ;-) God, no. I hate compressed audio. (Dolby Digital, at least.) (1) Dolby Digital is really old-old tech, predating MP3 by lots. What difference does it make when it was created? Perceptual coding was and is a work in progress. Progress was pretty rapid at the time that DD was introduced and the decade following it. Dolby AC-3 AKA Dolby Digital was introduced in 1991. It is a proprietary standard, and has not changed a lot over the years. MP3 has remained a work in progress since 1989. The rate at which MP3 coders were improved slowed down quite a bit after ca. 1998, but improvement may still be possible. You're not making sense. Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? Maybe you're a different Arny Krueger and have come to realize that these blind tests are ineffective. |
#95
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
In article , pj wrote:
Scott Dorsey wrote: William Sommerwerck wrote: Since the s-video output and the composite output are both NTSC, it is impossible for either the s-video output or the composite output to have *more* output than the NTSC output -- they *ARE* NTSC outputs. This might be true in practice, but "it ain't necessarily so". How would they not be NTSC? A case for S-Video in preference to Composite: Oh, there are many strong cases for S-Video over composite. But both are NTSC. The S-Video is also NTSC, it's just not RS-170. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#96
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"trotsky" wrote in message
news:MbDxj.54004$yE1.27091@attbi_s21... You're not making sense. Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? Maybe you're a different Arny Krueger and have come to realize that these blind tests are ineffective. It doesn't matter. Dolby Digital is so bad that you can hear its problems without comparing it with anything else. Before Arny objects... I was accustomed to listening to CD-format stereo from my LaserDisks. I was continually surprised and pleased with the great transparency, cleanliness, and "ease" of the sound. The first time I decoded a Dolby Digital signal ("The Incredibles") I could hear the difference -- flat, grainy, dry, blah sound. The audibility of lossy codecs varies with the quality of the playback system. Over my computer speakers (Monsoon planar magnetics), KUOW sounds fine. Not only is it clean and transparent, but I've never heard anything that I interpreted as an artifact. (This is the Microsoft codec.) |
#97
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"trotsky" wrote in message
news:MbDxj.54004$yE1.27091@attbi_s21 Arny Krueger wrote: "trotsky" wrote in message news:vACxj.1219$TT4.358@attbi_s22 Arny Krueger wrote: "William Sommerwerck" wrote in message "Arny Krueger" wrote in message ... "William Sommerwerck" wrote in message Yes, it's brilliant. (It's one of the great 20th century inventions.) But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth If we extrapolate this discussion to audio, then we have Willaim Sommerwerck, MP3 advocate! ;-) God, no. I hate compressed audio. (Dolby Digital, at least.) (1) Dolby Digital is really old-old tech, predating MP3 by lots. What difference does it make when it was created? Perceptual coding was and is a work in progress. Progress was pretty rapid at the time that DD was introduced and the decade following it. Dolby AC-3 AKA Dolby Digital was introduced in 1991. It is a proprietary standard, and has not changed a lot over the years. MP3 has remained a work in progress since 1989. The rate at which MP3 coders were improved slowed down quite a bit after ca. 1998, but improvement may still be possible. You're not making sense. Please clarify, because the questions that follow are not requests for clarification. Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? AFAIK, Dolby never claimed that DD was perfectly transparent. The MPEG group coder tests in the late 1990s showed that Dolby Digital was not sonically transparent and generally inferior to other, more modern codecs. Maybe you're a different Arny Krueger Nope. Just older and wiser. ;-) and have come to realize that these blind tests are ineffective. How so? The fact that AC-3 was a substandard codec based on the MPEG Group's blind tests was pretty well publicized by the MPEG and the AES. This was no doubt a bit of an embarrassment to Dolby. Dolby has been doing their own blind tests for decades. Dolby subsequently came out with a new multimodal system for coding and decoding audio known as Dolby TrueHD. In some modes, TrueHD is definitely sonically transparent. |
#98
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
William Sommerwerck wrote:
"trotsky" wrote in message news:MbDxj.54004$yE1.27091@attbi_s21... You're not making sense. Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? Maybe you're a different Arny Krueger and have come to realize that these blind tests are ineffective. It doesn't matter. Dolby Digital is so bad that you can hear its problems without comparing it with anything else. Before Arny objects... I was accustomed to listening to CD-format stereo from my LaserDisks. I was continually surprised and pleased with the great transparency, cleanliness, and "ease" of the sound. The first time I decoded a Dolby Digital signal ("The Incredibles") I could hear the difference -- flat, grainy, dry, blah sound. Agreed on all counts. The audibility of lossy codecs varies with the quality of the playback system. Over my computer speakers (Monsoon planar magnetics), KUOW sounds fine. Not only is it clean and transparent, but I've never heard anything that I interpreted as an artifact. (This is the Microsoft codec.) What are you trying to say? Are you saying the lossiness of DD would be audible over your computer speakers or not? |
#99
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Harsh, "aliased" sound with digital TV converter box.
The audibility of lossy codecs varies with the quality of the playback
system. Over my computer speakers (Monsoon planar magnetics), KUOW sounds fine. Not only is it clean and transparent, but I've never heard anything that I interpreted as an artifact. (This is the Microsoft codec.) What are you trying to say? Are you saying the lossiness of DD would be audible over your computer speakers or not? No, I'm saying that the Monsoons, good as they are, aren't Apogees. |
#100
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
In article ,
"William Sommerwerck" wrote: The first time I decoded a Dolby Digital signal ("The Incredibles") I could hear the difference -- flat, grainy, dry, blah sound. Ooo, nice description. -- Star Trek 09: No Shat, No Show. http://www.disneysub.com/board/noshat.jpg |
#101
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
In article "William Sommerwerck" writes:
No, I'm talking objective fact. Color-difference signals require less bandwidth than color-primary signals. I rather doubt that. Even small changes in small areas would produce the same bandwidth. However, the magnitude of the signal may be less. The critical thing is that *because of the limitations of human vision*, one can get away with reducing the bandwidth of the color difference signals. The original color difference signal may well have full bandwidth -- since the color difference signals vary with hue variation, even when the saturation remains the same. (They also vary with saturation change even with hue remaining the same.) Alan |
#102
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
"Alan" wrote in message
... In article "William Sommerwerck" writes: No, I'm talking objective fact. Color-difference signals require less bandwidth than color-primary signals. I rather doubt that. Even small changes in small areas would produce the same bandwidth. However, the magnitude of the signal may be less. Correct. But color-difference signals DON'T HAVE THOSE SMALL CHANGES. The critical thing is that *because of the limitations of human vision*, one can get away with reducing the bandwidth of the color difference signals. Not so. Think about it. Saturation (which is what the amplitude of the color-difference signal represents) "never" (well, hardly ever) changes as rapidly as luminance. The original color difference signal may well have full bandwidth -- since the color difference signals vary with hue variation, even when the saturation remains the same. (They also vary with saturation change even with hue remaining the same.) See above. This is the typical knee-jerk reaction to something someone hasn't bothered to think through. |
#103
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
Arny Krueger wrote:
"trotsky" wrote in message news:MbDxj.54004$yE1.27091@attbi_s21 Arny Krueger wrote: "trotsky" wrote in message news:vACxj.1219$TT4.358@attbi_s22 Arny Krueger wrote: "William Sommerwerck" wrote in message "Arny Krueger" wrote in message ... "William Sommerwerck" wrote in message Yes, it's brilliant. (It's one of the great 20th century inventions.) But -- and I will keep repeating this ad nauseum -- the reason color TV systems (of all sorts) can "get away" with reduced chroma bandwidth If we extrapolate this discussion to audio, then we have Willaim Sommerwerck, MP3 advocate! ;-) God, no. I hate compressed audio. (Dolby Digital, at least.) (1) Dolby Digital is really old-old tech, predating MP3 by lots. What difference does it make when it was created? Perceptual coding was and is a work in progress. Progress was pretty rapid at the time that DD was introduced and the decade following it. Dolby AC-3 AKA Dolby Digital was introduced in 1991. It is a proprietary standard, and has not changed a lot over the years. MP3 has remained a work in progress since 1989. The rate at which MP3 coders were improved slowed down quite a bit after ca. 1998, but improvement may still be possible. You're not making sense. Please clarify, because the questions that follow are not requests for clarification. Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? AFAIK, Dolby never claimed that DD was perfectly transparent. And your working definition for "perfectly transparent" is what, exactly? The MPEG group coder tests in the late 1990s showed that Dolby Digital was not sonically transparent and generally inferior to other, more modern codecs. At all bit rates? And again, what is the definition or "sonically transparent"--when people with Radio Shack stereos can tell the difference? Maybe you're a different Arny Krueger Nope. Just older and wiser. ;-) Yeah, I'll buy the older part. If you're saying blind test results have to be taken with a grain of salt then I'll buy the wiser part. and have come to realize that these blind tests are ineffective. How so? The fact that AC-3 was a substandard codec based on the MPEG Group's blind tests was pretty well publicized by the MPEG and the AES. Perhaps you can show us a cite for these results, then. This was no doubt a bit of an embarrassment to Dolby. Dolby has been doing their own blind tests for decades. Dolby subsequently came out with a new multimodal system for coding and decoding audio known as Dolby TrueHD. In some modes, TrueHD is definitely sonically transparent. Again, you are using a term without defining its meaning. |
#104
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"trotsky" wrote in message
news%Txj.55219$yE1.36314@attbi_s21 Arny Krueger wrote: "trotsky" wrote in message news:MbDxj.54004$yE1.27091@attbi_s21 Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? AFAIK, Dolby never claimed that DD was perfectly transparent. And your working definition for "perfectly transparent" is what, exactly? Passes a bypass test with under any relevant test condition without audible alternation. The MPEG group coder tests in the late 1990s showed that Dolby Digital was not sonically transparent and generally inferior to other, more modern codecs. At all bit rates? As typically used. And again, what is the definition or "sonically transparent"--when people with Radio Shack stereos can tell the difference? Relevant tests are used with selected, trained listeners. Listener sensitivity is essential. Please see ITU recommendation BS 1116, which is availble through the web. Maybe you're a different Arny Krueger Nope. Just older and wiser. ;-) Yeah, I'll buy the older part. If you're saying blind test results have to be taken with a grain of salt then I'll buy the wiser part. Let's put it this way - every test result must be considered in its context. Sighted tests for signal quality are generally so invalid that they need not be taken seriously at all. Blind test results are at least worth considering. and have come to realize that these blind tests are ineffective. How so? The fact that AC-3 was a substandard codec based on the MPEG Group's blind tests was pretty well publicized by the MPEG and the AES. Perhaps you can show us a cite for these results, then. Check the AES web site. They were published in the JAES some years back. This was no doubt a bit of an embarrassment to Dolby. Dolby has been doing their own blind tests for decades. Dolby subsequently came out with a new multimodal system for coding and decoding audio known as Dolby TrueHD. In some modes, TrueHD is definitely sonically transparent. Again, you are using a term without defining its meaning. Which term? I've used tons of them. I would expect that the readers of the newsgroups we are posting to know what most common audio terms mean. |
#105
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
"Arny Krueger" wrote in message
"trotsky" wrote in message news%Txj.55219$yE1.36314@attbi_s21 Arny Krueger wrote: "trotsky" wrote in message news:MbDxj.54004$yE1.27091@attbi_s21 Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? AFAIK, Dolby never claimed that DD was perfectly transparent. And your working definition for "perfectly transparent" is what, exactly? Passes a bypass test with under any relevant test condition without audible alternation. Correction: Passes a bypass test with under any relevant test condition without audible alteration. |
#106
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
On Feb 29, 7:15 am, "William Sommerwerck"
wrote: snip Not so. Think about it. Saturation (which is what the amplitude of the color-difference signal represents) "never" (well, hardly ever) changes as rapidly as luminance. You need to be careful here. While saturation is a function of color differences, it needs to be normalized by the intensity. Simple color differences are functions of both saturation and luminosity. Consider, for example, calculating saturation in the HSI coordinate system as illustrated in this link: http://homepages.inf.ed.ac.uk/rbf/CV....html#tth_sEc3 Similar examples for other coordinate systems can be found he http://en.wikipedia.org/wiki/Saturation_(color_theory) |
#107
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
Not so. Think about it. Saturation (which is what the amplitude of the
color-difference signal represents) "never" (well, hardly ever) changes as rapidly as luminance. You need to be careful here. While saturation is a function of color differences, it needs to be normalized by the intensity. That is PRECISELY the point. Subtracting Y from R, G, or B provides the normalization and produces a saturation -- color-difference -- signal from which brightness information has been removed. This is what we want. More than 50 years ago, Electronics magazine published pictures of the NTSC color signals, based on real scenes. The colors are completely "flat" -- they are of constant saturation, with no variation in brightness. It's important to understand that NTSC and PAL are non-redundant systems. None of the three signals contains information present in another. |
#108
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
Arny Krueger wrote:
"trotsky" wrote in message news%Txj.55219$yE1.36314@attbi_s21 Arny Krueger wrote: "trotsky" wrote in message news:MbDxj.54004$yE1.27091@attbi_s21 Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? AFAIK, Dolby never claimed that DD was perfectly transparent. And your working definition for "perfectly transparent" is what, exactly? Passes a bypass test with under any relevant test condition without audible alternation. A) That sentence makes no sense grammatically, and B) you have provided no definition for "passes a bypass test". You keep making the same mistakes over and over. The MPEG group coder tests in the late 1990s showed that Dolby Digital was not sonically transparent and generally inferior to other, more modern codecs. At all bit rates? As typically used. And again, what is the definition or "sonically transparent"--when people with Radio Shack stereos can tell the difference? Relevant tests are used with selected, trained listeners. Listener sensitivity is essential. Please see ITU recommendation BS 1116, which is availble through the web. This is silly. I'll ask again: can you define what you're talking about? What's a passing grade for "sonically transparent"--100%? 90%? If 80% of the trained listeners can't tell the difference, is it then "sonically transparent"? Then there's Bill Somerwerck's point: how good is the resolution of the equipment they're using? If the speakers are mediocre, that will skew the results. Maybe you're a different Arny Krueger Nope. Just older and wiser. ;-) Yeah, I'll buy the older part. If you're saying blind test results have to be taken with a grain of salt then I'll buy the wiser part. Let's put it this way - every test result must be considered in its context. Sighted tests for signal quality are generally so invalid that they need not be taken seriously at all. Blind test results are at least worth considering. Sure, if you believe in Jesus I guess you can believe in the vagaries of blind testing. and have come to realize that these blind tests are ineffective. How so? The fact that AC-3 was a substandard codec based on the MPEG Group's blind tests was pretty well publicized by the MPEG and the AES. Perhaps you can show us a cite for these results, then. Check the AES web site. They were published in the JAES some years back. Nice try, Arny. AES charges $5 for members and $20 for non-members for each paper on the topic. Again, please provide a cite for what you're talking about. This was no doubt a bit of an embarrassment to Dolby. Dolby has been doing their own blind tests for decades. Dolby subsequently came out with a new multimodal system for coding and decoding audio known as Dolby TrueHD. In some modes, TrueHD is definitely sonically transparent. Again, you are using a term without defining its meaning. Which term? I've used tons of them. I would expect that the readers of the newsgroups we are posting to know what most common audio terms mean. You have no working definition of "sonically transparent". Intellectually, you are about as credible as a crack addict. Are you a crack addict? |
#109
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
Arny Krueger wrote:
"Arny Krueger" wrote in message "trotsky" wrote in message news%Txj.55219$yE1.36314@attbi_s21 Arny Krueger wrote: "trotsky" wrote in message news:MbDxj.54004$yE1.27091@attbi_s21 Did Dolby do their homework and do sufficient blind tests to "prove" that their codec was transparent to people? AFAIK, Dolby never claimed that DD was perfectly transparent. And your working definition for "perfectly transparent" is what, exactly? Passes a bypass test with under any relevant test condition without audible alternation. Correction: Passes a bypass test with under any relevant test condition without audible alteration. You're still not speaking English. |
#110
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
"William Sommerwerck" wrote ...
Not so. Think about it. Saturation (which is what the amplitude of the color-difference signal represents) "never" (well, hardly ever) changes as rapidly as luminance. You need to be careful here. While saturation is a function of color differences, it needs to be normalized by the intensity. That is PRECISELY the point. Subtracting Y from R, G, or B provides the normalization and produces a saturation -- color-difference -- signal from which brightness information has been removed. This is what we want. The original reason for even matrixing R-G-B into Y-*-* was to preserve monochrome compatibility for those who have B&W receivers. And then to produce a color signal that could be relatively easily compressed and encoded onto a subcarrier and then decoded at the receiver. This is not necessarily "what we want" for those who prefer their video ucompressed and uncompromised. It was a kludge workaround to fit the 15-pound color signal into the 5-pound monochrome sack (channel bandwidth). More than 50 years ago, Electronics magazine published pictures of the NTSC color signals, based on real scenes. The colors are completely "flat" -- they are of constant saturation, with no variation in brightness. Then you were looking at the color difference signals. (Pb, Pr, etc.) after the luminance (Y) had been removed. We will have to disagree whether to call those signals "color". They are maybe "color difference" at best. If you saw the original Red Green Blue signals, they have plenty of contrast. It's important to understand that NTSC and PAL are non-redundant systems. None of the three signals contains information present in another. It is equally important to remember that in NTSC and PAL, the color-difference part of the signal is artifically frequency- limited to save bandwidth during transmission/storage. Any time you execute this kind of lossy compression, you irretrievably lose information. Whether you are talking about audio or video. |
#111
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
Richard Crowley wrote:
The original reason for even matrixing R-G-B into Y-*-* was to preserve monochrome compatibility for those who have B&W receivers. And then to produce a color signal that could be relatively easily compressed and encoded onto a subcarrier and then decoded at the receiver. There's really no future in it. People don't really _want_ color anyway. I'm waiting until it's perfected before I buy a color set. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#112
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
"Scott Dorsey" wrote ...
Richard Crowley wrote: The original reason for even matrixing R-G-B into Y-*-* was to preserve monochrome compatibility for those who have B&W receivers. And then to produce a color signal that could be relatively easily compressed and encoded onto a subcarrier and then decoded at the receiver. There's really no future in it. People don't really _want_ color anyway. I'm waiting until it's perfected before I buy a color set. You missed the peak. Even as screen sizes increase and we get "High Definition" 16x9 video, lossy compression is being cranked up and turning video into watery puddles of what used to be pictures. I was trying to watch "Bone Detectives" on the Discovery Channel on DishNetwork last night and the compression was so high that it couldn't even keep up with the guy walking across the sand. It was almost un-watchable on my 13-inch video monitor. It would have looked like water- damaged wallaper on a big screen TV. For the decline of technical quality, along with the decline of programming worth watching, I'm letting my satellite subscription just expire. |
#113
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
"Richard Crowley" wrote in message
... "William Sommerwerck" wrote ... Not so. Think about it. Saturation (which is what the amplitude of the color-difference signal represents) "never" (well, hardly ever) changes as rapidly as luminance. You need to be careful here. While saturation is a function of color differences, it needs to be normalized by the intensity. That is PRECISELY the point. Subtracting Y from R, G, or B provides the normalization and produces a saturation -- color-difference -- signal from which brightness information has been removed. This is what we want. The original reason for even matrixing R-G-B into Y-*-* was to preserve monochrome compatibility for those who have B&W receivers. And then to produce a color signal that could be relatively easily compressed and encoded onto a subcarrier and then decoded at the receiver. This is not necessarily "what we want" for those who prefer their video ucompressed and uncompromised. It was a kludge workaround to fit the 15-pound color signal into the 5-pound monochrome sack (channel bandwidth). More than 50 years ago, Electronics magazine published pictures of the NTSC color signals, based on real scenes. The colors are completely "flat" -- they are of constant saturation, with no variation in brightness. Then you were looking at the color difference signals. (Pb, Pr, etc.) after the luminance (Y) had been removed. We will have to disagree whether to call those signals "color". They are maybe "color difference" at best. If you saw the original Red Green Blue signals, they have plenty of contrast. It's important to understand that NTSC and PAL are non-redundant systems. None of the three signals contains information present in another. It is equally important to remember that in NTSC and PAL, the color-difference part of the signal is artifically frequency- limited to save bandwidth during transmission/storage. Any time you execute this kind of lossy compression, you irretrievably lose information. Whether you are talking about audio or video. I'm not going to beat this to death, because what I've said is 100% correct, and a bit of though will confirm that. Simply limiting the bandwidth of a signal is not "compression" in any ordinary sense. The real compression -- which is not lossy -- is subtracting Y from the primary color signals. This permits the color-difference signals to more "advantageously" use their limited bandwidth. I've stopped discussing this. A few nights from now, when you're mulling this over in bed, and the light goes on, you can post a "Oh, yeah... Now I get it." response. |
#114
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
"William Sommerwerck" wrote ...
I'm not going to beat this to death, because what I've said is 100% correct, and a bit of though will confirm that. Simply limiting the bandwidth of a signal is not "compression" in any ordinary sense. It most certainly is information compression in the truest sense. The people that worked on the telephone system have known it for nearly a century. Perhaps you need a bit more thought. The real compression -- which is not lossy -- is subtracting Y from the primary color signals. This permits the color-difference signals to more "advantageously" use their limited bandwidth. That is not compression at all. That is simply changing the format of the information. Your view of this appears to be fundamentally incorrect. I've stopped discussing this. A few nights from now, when you're mulling this over in bed, and the light goes on, you can post a "Oh, yeah... Now I get it." response. Perhaps YOU will have that experience. I don't need it. |
#115
Posted to rec.audio.pro
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(now) color difference signals
"Richard Crowley" wrote in message ... "Scott Dorsey" wrote ... There's really no future in it. People don't really _want_ color anyway. I'm waiting until it's perfected before I buy a color set. You missed the peak. Even as screen sizes increase and we get "High Definition" 16x9 video, lossy compression is being cranked up and turning video into watery puddles of what used to be pictures. No kidding. I've watched CNN a couple of times in the last month (primaries), on a large screen, and it was absolutely unwatchable. The commentator's mouth looked like a squashed blintz constantly changing in shape as its borders dissolved and re-formed. If I'd seen that in the Sixties at a light show I would have thought "groovy", but as it was I got queasy and left. Digital TV makes everything look like a bad acid trip. It didn't help that the audio was badly out of sync. Peace, Paul |
#116
Posted to rec.audio.pro
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(now) color difference signals
No kidding. I've watched CNN a couple of times in the last month
(primaries), on a large screen, and it was absolutely unwatchable. The commentator's mouth looked like a squashed blintz constantly changing in shape as its borders dissolved and re-formed. If I'd seen that in the Sixties at a light show I would have thought "groovy", but as it was I got queasy and left. Digital TV makes everything look like a bad acid trip. How large is large? I own two IDTVs (32" and 36") , and their image quality is generally quite good. |
#117
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
"Richard Crowley" wrote in message
... "William Sommerwerck" wrote ... The real compression -- which is not lossy -- is subtracting Y from the primary color signals. This permits the color-difference signals to more "advantageously" use their limited bandwidth. That is not compression at all. That is simply changing the format of the information. Your view of this appears to be fundamentally incorrect. Changing the format is one way of presenting the information in a more-compact, more-useful fashion. The "compression" produced by subtracting the luminance is the removal of redundant information. I've stopped discussing this. A few nights from now, when you're mulling this over in bed, and the light goes on, you can post a "Oh, yeah... Now I get it." response. Perhaps YOU will have that experience. I don't need it. You will. YOU WILL... |
#118
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
On Feb 28, 1:56 pm, (Scott Dorsey) wrote:
In article , pj wrote: Scott Dorsey wrote: William Sommerwerck wrote: Since the s-video output and the composite output are both NTSC, it is impossible for either the s-video output or the composite output to have *more* output than the NTSC output -- they *ARE* NTSC outputs. This might be true in practice, but "it ain't necessarily so". How would they not be NTSC? A case for S-Video in preference to Composite: Oh, there are many strong cases for S-Video over composite. But both are NTSC. The S-Video is also NTSC, it's just not RS-170. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." Unless the S-video signal is based on the PAL standard! :-) |
#119
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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(now) color difference signals
On Feb 29, 1:51*pm, "William Sommerwerck"
wrote: "Richard Crowley" wrote in message ... "William Sommerwerck" *wrote ... The real compression -- which is not lossy -- is subtracting Y from the primary color signals. This permits the color-difference signals to more "advantageously" use their limited bandwidth. That is not compression at all. That is simply changing the format of the information. Your view of this appears to be fundamentally incorrect. Changing the format is one way of presenting the information in a more-compact, more-useful fashion. The "compression" produced by subtracting the luminance is the removal of redundant information. I've stopped discussing this. A few nights from now, when you're mulling this over in bed, and the light goes on, you can post a "Oh, yeah... Now I get it." response. Perhaps YOU will have that experience. I don't need it. You will. YOU WILL... Just FYI, the transcoding from RGB to Y, R-Y, B-Y is a lossless transform and does not one iota of bandwidth change _until_ you run the components through the bandpass filters on the way to the balanced modulators. Also, there most certainly is equiband encoding going on. I was working on a BetaCam SP just yesterday and the filters in the encoder have the same part numbers. How could they be differrent? The Sony broadcast cameras are the same story as is the Accom D-122 digital encoder - all of which were VERY common in Hollywood. You'd have a mauch harder time finding a true IQ encoder. As I said earlier, the last IQ encoder I saw was an RCA studio camera from 1976 GG |
#120
Posted to alt.video.digital-tv,rec.arts.tv,rec.audio.pro,sci.engr.television.advanced,alt.tv.tech.hdtv
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Harsh, "aliased" sound with digital TV converter box.
jwvm wrote:
On Feb 28, 1:56 pm, (Scott Dorsey) wrote: In article , pj wrote: Scott Dorsey wrote: William Sommerwerck wrote: Since the s-video output and the composite output are both NTSC, it is impossible for either the s-video output or the composite output to have *more* output than the NTSC output -- they *ARE* NTSC outputs. This might be true in practice, but "it ain't necessarily so". How would they not be NTSC? A case for S-Video in preference to Composite: Oh, there are many strong cases for S-Video over composite. But both are NTSC. The S-Video is also NTSC, it's just not RS-170. Unless the S-video signal is based on the PAL standard! :-) Or SECAM for that matter! --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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