Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion. Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules. |
20th June 2005, 17:23 | #1 | Link |
Registered User
Join Date: Feb 2005
Location: Calgary, Canada
Posts: 139
|
Sample HD MPEG-1 Clip...
Hey guys, found this site just now. They are saying that with their MPEG-1 VBR (~5mbps) you can fit a 2 hour HD video on standard DVDs. Downloaded their test HD demo and it does look pretty good -- BUT, since I am no video guru I am wondering if someone can explain to me how this is different than MPEG-2/ASP/AVC.
Main site, http://www.digigami.com/megapeg/samples.php Download HD demo, http://www.digigami.com/megapeg/samp...Likely_PSA.mpg Thanks!! |
21st June 2005, 11:16 | #3 | Link |
Life's clearer in 4K UHD
Join Date: Jun 2003
Location: Notts, UK
Posts: 12,227
|
Actually, there's nothing new at generating Mpeg1 encodes at high-def resolutions... I've been doing it more than five years for use at exhibition stands!
As with Mpeg2 and Mpeg4, Mpeg1 has really improved as a codec in recent years.... It's just a real shame the majority of people still associate it with VCD (and VCD bit-rates). By the way, for some reason the "Least_Likely_PSA.mpeg" sample has been given aspect ratio signalling. After re-signalling to 1:1, the encode looks fine Cheers
__________________
| I've been testing hardware media playback devices and software A/V encoders and decoders since 2001 | My Network Layout & A/V Gear |
|
22nd June 2005, 13:36 | #6 | Link |
Satsuki'S Softs Maker
Join Date: Feb 2003
Posts: 192
|
this sample is very dark and in a 2.35 AR => hight compressibility.
it as also a lots a block in some aeras. i've tested and used a lot mpeg1 and mpeg2, with hdtv here's MY visual impression: hdtv mpeg2 > 10 mbps looks good. hdtv mpeg1 > 15 mbps looks good also. hdtv mpeg2 < 6 mbps looks like crap. hdtv mpeg1 < 9 mbps looks like crap. with a very good mpeg1 encoder with custom matrix, and 3 or more passes, i think it can do good looking HDTV quality around 9-10mbps, less than that is a dream. ps: i have better result in encoding mpeg1 with quenc than with tmpgenc (and it's free). ps2: if it's for hdtv archiving on DVD media, just use mpeg2, you will always have a better quality, and all graphics card (since around 1999-2000) have full mpeg2 hardware decoding ++ Last edited by Shinobu; 22nd June 2005 at 13:40. |
8th July 2005, 10:50 | #8 | Link | |
Digigami
Join Date: Jul 2005
Location: Los Angeles, CA
Posts: 182
|
Quote:
For standard 24p encoding, there are few gains to be had, at least, that is my experience as the developer of MegaPEG and MPressionist. Also, you refer to block artifacts in our MPEG-1 HD sample. This sample is designed to illustrate the use of MPEG-1 as a HD streaming/delivery format, not as an archival format. I am curious to know what decoder you are using to evaluate the stream. The diagnostic tool I use primarily is MPressionist, and it includes both highly-accurate (reference) and fairly-accurate (commonly-implemented) IDCT algorithms. My guess is that if you are seeing visible artifacts then the IDCT implementation of your decoder software is not conforming to the MPEG standard. I've reviewed our HD stream in a number of players, including Apple's MPEG-2 decoder (MPEG-2 playback component), MPressionist, VideoLAN and Windows Media Player, and no artifacts are visible under normal viewing conditions, which is to say, the same conditions one would use when watching TV. Could you describe the playback environment you are using? Thanks. Gen Kiyooka -------------------------------------------------- Digigami MegaPEG MPEG-2 Encoder - people disagree as to whether it's any good. MPressionist MPEG-2 Analyzer - no disagreements with this one, everybody likes it. Last edited by digigami; 23rd December 2005 at 23:25. |
|
22nd December 2005, 21:35 | #9 | Link |
Registered User
Join Date: Jan 2002
Posts: 332
|
for info
http://www.digigami.com/index.html Mpeg2 better than h264 ? What H264 encoder is used for the comparaison? |
23rd December 2005, 03:00 | #10 | Link | |
Registered User
Join Date: May 2003
Posts: 328
|
Quote:
Hence, as you can guess I'm really wondering what kind of nitro you load into your tractors to make them so good Obviously I'm not asking you to unveil your secrets but maybe you could at least enlight us with some technical clarifications with regard to your claims : encoding conditions (resolutions, bitrate, rate control constraints, etc.), which H.264 did you compare to and how it was set, how did you compare, and what makes you say which result is better than the other (objective metrics, subjective assessment ?), etc. Thanks ! |
|
23rd December 2005, 06:43 | #11 | Link |
Registered User
Join Date: Apr 2002
Location: Germany
Posts: 4,926
|
@easyfab and bobololo
looking here http://digigami.in-long-beach-ca.com...-VBR/commandN/ it seems he compares with *cough* apple quicktime h.264 :P (no comment)
__________________
all my compares are riddles so please try to decipher them yourselves :) It is about Time Join the Revolution NOW before it is to Late ! http://forum.doom9.org/showthread.php?t=168004 |
23rd December 2005, 14:35 | #13 | Link | |
Registered User
Join Date: Jan 2002
Location: Finland
Posts: 522
|
Quote:
Last edited by JohnV; 23rd December 2005 at 14:37. |
|
23rd December 2005, 19:24 | #14 | Link | |
Digigami
Join Date: Jul 2005
Location: Los Angeles, CA
Posts: 182
|
Willing to Compare
Quote:
Thanks for the responses. Currently, the primary marketing thrust of H.264 is that it can compress HD feature films down into the same bitrates as standard definition DVD. Our marketing is aimed at demonstrating that MPEG-2 VBR is a viable alternative to H.264 for this purpose. As I stated in my blog, I am willing to do comparative analysis. I am not interested in comparing 5s test clips of random camcorder footage, but rather professionally produced feature film/motion graphics/TV content. It is not strictly marketing. Both our MPEG-1 and MPEG-2 VBR encoders are producing HD bitstreams with average bitrates well below 9mbs/s. If you look about 1 year ago we were promoting our MPEG-1 encoder as an alternative to Real/Flash for streaming video. You will also find a 1/2 D1 NTSC MPEG-2 sample for DVD on our web site at 0.5mbs/s. There's a consistent theme here - not an isolated incident. In the last 24 hours I produced a 1280x720x50 fps version of the Mako Shark Club Jacket sample to HD-DVD specs, average bitrate 11 mbits/s and the quality is essentially perfect. In order for MPEG-2 VBR to be a viable alternative to H.264, it does not have to be better, it merely needs to be comparable. As far as the quality goes, the clips on our site speak for themselves. Gen -------------------------------------------------- Digigami MegaPEG MPEG-2 Encoder - people disagree as to whether it's any good. MPressionist MPEG-2 Analyzer - no disagreements with this one, everybody likes it. Last edited by digigami; 23rd December 2005 at 23:26. |
|
23rd December 2005, 19:32 | #15 | Link | |
Digigami
Join Date: Jul 2005
Location: Los Angeles, CA
Posts: 182
|
commandN Sample -> Recompress it Smaller Than MPEG-1
Quote:
My personal belief is that there are fundamental lower limits (called the entropy of a clip) which can be approached by any good encoder technology but reducing further one runs into the law of diminishing returns. Also, if you have a sample you'd also like to compare with, I prefer to start with a high quality source. Gen -------------------------------------------------- Digigami MegaPEG MPEG-2 Encoder - people disagree as to whether it's any good. MPressionist MPEG-2 Analyzer - no disagreements with this one, everybody likes it. Last edited by digigami; 23rd December 2005 at 23:26. |
|
23rd December 2005, 19:41 | #16 | Link | |
Digigami
Join Date: Jul 2005
Location: Los Angeles, CA
Posts: 182
|
Quote:
For H.264 samples I use what I can find. If you have suggestions, I'd like to hear them. BTW, as I am not an H.264 expert, what features does H.264 have for coding interlaced video? -------------------------------------------------- Digigami MegaPEG MPEG-2 Encoder - people disagree as to whether it's any good. MPressionist MPEG-2 Analyzer - no disagreements with this one, everybody likes it. Last edited by digigami; 23rd December 2005 at 23:26. |
|
23rd December 2005, 19:51 | #17 | Link | |
Digigami
Join Date: Jul 2005
Location: Los Angeles, CA
Posts: 182
|
Comparing
Quote:
http://www.digigami.com/mpressionist...n=comparesplit I wrote this tool specifically so I can have these kinds of discussions without the dialogue descending into mud-slinging and religious fervour. I can compare side by side with split screen: Source/MPEG-2 Source/H.264 MPEG-2/H.264 MPEG-2/MPEG-2 Also, can compare pixel residue (actual per-pixel frame differences) which is useful for picking up differences too fine for the eyes to see. How do you compare? Gen -------------------------------------------------- Digigami MegaPEG MPEG-2 Encoder - people disagree as to whether it's any good. MPressionist MPEG-2 Analyzer - no disagreements with this one, everybody likes it. Last edited by digigami; 23rd December 2005 at 23:26. |
|
23rd December 2005, 19:53 | #18 | Link | |
Testeur de codecs
Join Date: May 2003
Location: France
Posts: 2,484
|
Quote:
Well 11 Mbps for 1280*720*50 or 1920*1088*25 is very high bitrate for H264. Apple QT7 AVC done very good result with 1920*1088*25 trailers sources (very uncompressible sources) and it isn't by far the best AVC encoder. Try with 1.1 Mbps and with good H264 codec and see the result ... !!! Here little H264 1280*720 encoding at 1250 Mbps ... try to make that with MPEG1/2 ... I test your demo encoder and it isn't visually very better than the other popular MPEG2 encoder. Say "MPEG2 is better than H264" (source? bitrate? average quant? subjective? objective?) is totaly ridiculous ... I have little challenge for you : try to prove that your MPEG2 encoder is the best for metric ... http://forum.doom9.org/showthread.php?t=98633
__________________
Le Sagittaire ... ;-) 1- Ateme AVC or x264 2- VP7 or RV10 only for anime 3- XviD, DivX or WMV9 Last edited by Sagittaire; 23rd December 2005 at 20:00. |
|
23rd December 2005, 20:35 | #19 | Link | |
Digigami
Join Date: Jul 2005
Location: Los Angeles, CA
Posts: 182
|
Quote:
I will look at it. From what source did you obtain the trailer? DVD? - Gen -------------------------------------------------- Digigami MegaPEG MPEG-2 Encoder - people disagree as to whether it's any good. MPressionist MPEG-2 Analyzer - no disagreements with this one, everybody likes it. Last edited by digigami; 23rd December 2005 at 23:27. |
|
23rd December 2005, 20:36 | #20 | Link | |
Digigami
Join Date: Jul 2005
Location: Los Angeles, CA
Posts: 182
|
Does not Play - Suggestions...
Quote:
What playback system do you recommend. Also, what source was used in the compression? Gen -------------------------------------------------- Digigami MegaPEG MPEG-2 Encoder - people disagree as to whether it's any good. MPressionist MPEG-2 Analyzer - no disagreements with this one, everybody likes it. Last edited by digigami; 23rd December 2005 at 23:27. |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|