PBS switching to H.264?
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Yeah, I noticed the improved picture. Channel 8.4 looks better for sure
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That's... fascinating. For all of the channels, or only subchannels?
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Maybe the main PBS channel looks a little sharper, too. But I noticed the biggest difference on subchannel 8.4. It was pretty horrible before.
EDIT: I noticed this picture improvement maybe a month or so ago. Channel 8.2 (Create) looks sharper as well.
I don't see a huge difference visually on the main channel from last weekend's Austin City Limits, but I'll get a better idea tonight when I record Nova. It went from 1080i at about 8Mbps to 720p at about 3.5Mbps. Obviously that frees up a lot of subchannel space (that I never watch).
ATSC has always supported H.264, I've just never seen it used in the Houston market. Any TiVo newer than the original Series 3 with the OLED display should be fine.
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FYI: KUHT - Wikipedia
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Start worrying. Just north of San Jose, Comcast has started MPEG4 encoding some OTA at ~4.2Mbps. 717 (60.1 Independent owned by 22.1 PBS), 704 (4.1 MyNetwork), 709, 710 (9.1/54.2, 54.1/9.2 PBS). ABC, FOX, CBS remain MPEG2 and 10-13Mpbs. I didn't check the other channels I do not watch. Of the ones I watch, OTA transmission is still MPEG2. Most of the subchannels are still SD.
About half the shows I download are missing the video track.
Audio only on some linked Comcast broadcast channels - SF Bay Area
Except most HDTV's do NOT support H.264...so I guess this means those viewers (w/out H.264 capable TV's) get zip now from this station...
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I noticed a while back my PBS "looked better"... I'm wondering if they switched as well.
Not always. Per Wikipedia, "In July 2008, ATSC was updated to support the ITU-T H.264 video codec." Prior to now, I've only seen it on a single local subchannel here, Stadium (45.4 Baltimore). It's been there a while. Only newer TVs can pick it up. When I mentioned it on DSLReports, some dumbass refused to believe me.
I stand corrected, but apparently the DTV implementation in the US didn't happen for another year or so. I would assume that most TVs built with an ATSC tuner should be fine.Not always. Per Wikipedia, "In July 2008, ATSC was updated to support the ITU-T H.264 video codec." Prior to now, I've only seen it on a single local subchannel here, Stadium (45.4 Baltimore). It's been there a while. Only newer TVs can pick it up. When I mentioned it on DSLReports, some dumbass refused to believe me.
Digital television transition in the United States - Wikipedia
You don't get uncompressed video over broadcast or cable, ever.* So, that's not the issue. The issue is, given a fixed amount of bits, how do you best make use of them? H.264 can, generally, make better use of them than MPEG-2 can. They're both lossy codecs, but H.264 will, for a given bit rate, tend to come closer to reproducing the original image than MPEG-2 will.
Now, if you started from an MPEG-2 source and recompressed it with H.264, then yeah, that's gonna be worse, because each step is lossy. But if you start from the uncompressed source, and just compress it once with each codec, separately, to about the same size -- then H.264 will look better. The latter would, presumably, be what the TV stations are doing. (Comcast is another issue.)
* Uncompressed video is measured in gigabits per second -- almost 1.5 Gb/s for 1080i. It has to be compressed to 19.2 megabits per second, or less, to fit into an ATSC TV channel. That's about 78:1.
That's not the DTV implementation, that's the analog shutdown. ATSC was on air since the late 1990's. I personally have HD OTA recordings dating to 2002.
I recorded Nova this week on both Comcast & OTA in Houston area this week. Nova on OTA was MPG-2 with a 1920x1080 resolution, 29.970 fps w/ 7.36 kb/s stream and Comcast was their normal overly compressed 1280x720 resolution, 59.950fps w/ 3.5 kb/s stream.
Upon further review you're absolutely right - Nova was MPEG-2. After seeing my latest Austin City Limits recording (s45e06 Vampire Weekend) I just assumed that the switch to H.264 was a done deal. My bad, but both recordings were made on the same OTA Roamio. Maybe it's a work in progress.
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