Will Warner support Blu-ray?

[iknowall]

It's funny how you backed away from the universal claim you made when faced with a clear counterpoint.

No i always talked in terms of video, wich is where i have experience. Every claim i made was about video encoding... would not make sense for me talking about pictures.

The fact that it's a picture instead of a video is irrelevant.

No it is not because you deal with a video codec wich have it's compression limit, and these resctiction are not the same what you found when you compress an images.

If you not have experience with video editing and encoding, i understand that you say this.

Do you have a clue of the various video codecs and what limitation each codec have ?

For example the dv codec have a compression of 6:1 and a bit rate of 25 Mb/sec. ,
you can' t change the bit rate, nor the compression ratio, so how in the hell can you make a dv file bigger or smaller ?



If 1 hour of dv video take about 13gb, and you want to compare it to the mpeg4 codec to see wich one is the better codec, how in the hell can you encode the same movie and have a file of the same size ?

Dude you can set the higest bit rate available , the lowest compression available , but beleave me, you will never be able to compress 1 hour of movie in mpeg4 and make it a 13gb life size. No way you can do this.


So wharever you do the movie compressed with the dv codec will look a lot better whan the one compressend with the mpeg4 codec , in fact dv codec is less compressed, have an higer bit rate, and have a better quality.

Anyway, I think I finally get the gist of your position. To insert arbitrary numbers, I think you mean that MPEG4 can go from 100 Kbps to 10 Mpbs whereas MPEG2 can go from 500 Kbps to 54 Mbps. Is that roughly what you mean? If so, it seems within reason though not proven.

This is what i mean, every codec have a limitation, in term of bit rate , compression ratio, resolution, wich you can't change.

Sometimes you can have a fixed rate like the dv codec and you can't change anything, sometimes like with mpeg2 and mpeg4 you can change the bit rate and other aspect of the encoding that are not fixed, making the video with an higer quality , but within certain limits.

And like i said, these limits are totally different whan the limits what you found in the image compression, so that's why make no sense comparing the video encoding to the image.

 

[iknowall]

It's relevant because it shows how some compression types are superior to others.

it's irrelevant because you will never be albe to have the same situation when you encode a video.

JPEG2000 will produce the same quality image as JPEG at in a smaller file, it's compressing it more AND producing a superior image. This is the point you are refusing to accept.

So if you have a 10 mb jpeg and you can have 10kb jpeg2000 file with a better quality ?

i higly dubt that.

You can compress more AND have superior quality,

If you can change physics laws sure you can.

Show me how in the hell the mpeg4 codec can make a better encoding image than the dv codec. Dv codec is also better whan mpeg2 codec, because is a lot less compressed.

If i have a movie and i encode it using the dv codec and using the mpeg4 codec , i assure you the dv codec will preserve all the original detail and i will lose not that much quality,
but when i encode in mpeg4 i get a lot of dawnsampling compression that result in a worst image.

some codecs are better than others and MPEG4 is superior to MPEG2 simple as that.

Mpeg4 can't do many things that mpeg2 can do so explain in why is superior please.

Mpeg4 can't have less compression, so can't keep intact the image original information like mpeg2 can, period.

Like i said, unless you can change physic laws, if you lose some quantity of information during the encoding , you can't after magically recreate it.

 

[iknowall]

I would like to see how anyone can get better picture quality with 1Mb/s 640x480 using MP2 vs MP4(AVC)...

MPEG-2 video is not optimized for low bit-rates (less than 1 Mbit/s), it is made for bitrate up to at least 3 Mbit/s , try to compress with mpeg2 at 1Mb/sec. and you will get an unwatchable video with a lot of artifact.

Overvise try to mach the quality of an mpeg2hd 160mbit/sec. video. with an mpeg4hd video.

Good luck.

 

[iknowall]

If so, it seems within reason though not proven.

Well i have no need to prof this it is just mat.

More you compress, less bitrate your video have, because if 1 hour of dv video take 13gb, this mean that in 1 second it take about 3.6 mb, with give it a 3.6mb/sec. bitrate.

If i compress the movie, for example with a 41:1 compression ratio, the file will be 40 times smaller, for example 13 gb / 40 = 325mb , so you have a file 40 times smaller
for 1 hour of video with translate in a bit rate of 0,09 mb/sec.


You see after compress the video you get a lower bit rate, so this make you to understant why mpeg4 have a certain range of bitrate avaible.

 

[iknowall]

Well i have no need to prof this it is just mat.

More you compress, less bitrate your video have, because if 1 hour of dv video take 13gb, this mean that in 1 second it take about 3.6 mb, with give it a 3.6mb/sec. bitrate.

If i compress the movie, for example with a 40:1 compression ratio, the file will be 40 times smaller, for example 13 gb / 40 = 325mb , so you have a file 40 times smaller
for 1 hour of video with translate in a bit rate of 0,09 mb/sec.


You see after compress the video you get a lower bit rate, so this make you to understant why mpeg4 have a certain range of bitrate avaible.

Edit fixed little error.

 

[Shifty Geezer]

iknowall : I appreciate kinda where you're coming from but I'm not really understanding how it works. Can you please answer these three questions...

1) You have a digital uncompressed master that's 100 GB in size. With mpeg2 you compress it with settings that it's 1/6th the size, 17 GB in size. With mpeg4 you compress the master to 1/2ve it's size, 50 GB. Which will have the better image quality?

2) You have a digital uncompressed master that's 100 GB in size. With mpeg2 you compress it with settings that it's 1/2ve the size, 50 GB in size. With mpeg4 you compress the master to 1/6th it's size, 17 GB. Which will have the better image quality?

3) You have a digital uncompressed master that's 100 GB in size. With mpeg2 you compress it with settings that it's 1/2ve the size, 50 GB in size. With mpeg4 you compress the master to 1/2ve it's size, 50 GB. Which will have the better image quality?

 

[iknowall]

iknowall : I appreciate kinda where you're coming from but I'm not really understanding how it works. Can you please answer these three questions...

Sure

1) You have a digital uncompressed master that's 100 GB in size.
With mpeg2 you compress it with settings that it's 1/6th the size, 17 GB in size.
With mpeg4 you compress the master to 1/2ve it's size, 50 GB. Which will have the better image quality?

You can't do this . The lowest compression you can get with mpeg4 is something like 1/40
of the size . You will be never able to compress in mpeg4 with a 1:2 compression ratio , it's not an mpeg4 capability.

1:2 compression is something used with a professional loseless codec, ,means a quality very close to the original master.

just think that the dvcprohd codec, a professional codec , use a compression of 7:1

 

[Shifty Geezer]

Okay, so that's why you're saying MPEG4 won't work - because it's minimum compression ratio is of lower visual quality than the lower compression rates of MPEG2. What you're saying is that where a 100GB film can be compressed to 25 GB via MPEG2, the largest size you'de get from MPEG4 is 2.5 GB with the associated loss of data fidelity, and that's why given the substantial storage capacity of BluRay, using MPEG4 is a bad idea.

I'm guessing those arguing against this are assuming MPEG4 compression can be set to the same amount as MPEG2, same as me, and don't realise that MPEG4 has a minimum level of compression way below that.

Can anyone confirm this? From the MPEG's paper on MPEG4 I'm getting...

3.5.1 Formats Supported
The following formats and bitrates are be supported by MPEG-4 Visual :

• bitrates: typically between 5 kbit/s and more than 1 Gbit/s
• Formats: progressive as well as interlaced video
• Resolutions: typically from sub-QCIF to 'Studio' resolutions (4k x 4k pixels)

3.5.2 Compression Efficiency

• For all bit rates addressed, the algorithms are very efficient. This includes the compact coding of textures with a quality adjustable between "acceptable" for very high compression ratios up to "near lossless".
• Efficient compression of textures for texture mapping on 2-D and 3-D meshes.
• Random access of video to allow functionalities such as pause, fast forward and fast reverse of stored video.

1 Gb/s sounds nowhere near 1/40th the size. 1920x1080x24bitx30fps is 1.5 Gbits per second, so MPEG4 should be able to get as low as a 3:2 compression

 

[deathkiller]

Sure



You can't do this . The lowest compression you can get with mpeg4 is something like 1/40
of the size . You will be never able to compress in mpeg4 with a 1:2 compression ratio , it's not an mpeg4 capability.

1:2 compression is something used with a professional loseless codec, ,means a quality very close to the original master.

just think that the dvcprohd codec, a professional codec , use a compression of 7:1

Then why using the codec x264 at lowest compresion I can get 1:12 ratio (compared with raw RGB, 500KB:6MB per frame at 1920x1080) using quantizer 0.

The result may be out of the MP4 standar but you can obtain it and play it.

 

[iknowall]

Okay, so that's why you're saying MPEG4 won't work - because it's minimum compression ratio is of lower visual quality than the lower compression rates of MPEG2. What you're saying is that where a 100GB film can be compressed to 25 GB via MPEG2, the largest size you'de get from MPEG4 is 2.5 GB with the associated loss of data fidelity, and that's why given the substantial storage capacity of BluRay, using MPEG4 is a bad idea.

I'm guessing those arguing against this are assuming MPEG4 compression can be set to the same amount as MPEG2, same as me, and don't realise that MPEG4 has a minimum level of compression way below that.

Can anyone confirm this? From the MPEG's paper on MPEG4 I'm getting...
1 Gb/s sounds nowhere near 1/40th the size. 1920x1080x24bitx30fps is 1.5 Gbits per second, so MPEG4 should be able to get as low as a 3:2 compression

Actually the codec h.264 support a max bit rate of 29.4Mbps , so i don't know where the 1.5 gbit sec. came from, but it is impossible to get a bit rate like that from the actual codec.

29.4mbps

Compression Ratio: 29.4 Mbits/sec = 3.265 MB/sec, that's about 55:1 compression starting from 10 bit 4:2:2


To have a 1.5gb/sec. you have to eraze all the compression capabilities of the mpeg4 codec, and this means that with a bit rate of 1.5 gb/sec. using the mpeg4 codec will give you no visual advantage , because it don't compress the image so what's the point of using the mpeg4 codec ?

Theorically with a bit rate of 1.5dgit/sec. you have a 1:1 compression, so no compression,
and an mpeg4hd movie with that bit rate will look identiocal at an mpeg2 hd movie with a bit rate og 1.5gb/sec , because nor the mpeg2 nor the mpeg4 touch the image.

 

[iknowall]

Then why using the codec x264 at lowest compresion I can get 1:12 ratio (compared with raw RGB, 500KB:6MB per frame at 1920x1080) using quantizer 0.

The result may be out of the MP4 standar but you can obtain it and play it.

Because bigger is the file , more compression you need to match the max bit rate , so if you have to compress an hd video master of about 2 hour, you will never be able to do with am 1:12 ratio , because this would need a bit rate over the max bit rate used from the codec.

 

[Shifty Geezer]

Actually the codec h.264 support a max bit rate of 29.4Mbps , so i don't know where the 1.5 gbit sec. came from,

Well it came from the mpeg website
http://www.chiariglione.org/mpeg/standards/mpeg-4/mpeg-4.htm
Chapter 3.5

This might be a later set of standards than are present in conventional MPEG4 though?

 

[iknowall]

1920x1080x24bitx30fps is 1.5 Gbits per second, so MPEG4 should be able to get as low as a 3:2 compression[/FONT][/B]

This is a theorical number, theorically you can have every bit rate erazing the compression capabilities . But this means that you make the mpeg4 coded the same as another codec, so you make the use of it useless.

Compression = bitrare , where is not way to excape from this

 

[iknowall]

Well it came from the mpeg website
http://www.chiariglione.org/mpeg/standards/mpeg-4/mpeg-4.htm
Chapter 3.5

This might be a later set of standards than are present in conventional MPEG4 though?

This number is just because a theorical number, the commercial codec wont let you have such an hi bitrate.

You have a rigorous standard where number are fixed, overvise you lose all the advantage of using this codec.

So just because you can't have a 1:2 compression with the mpeg4 codec used for hd-dvd and blue ray this do not means that a professional version can't be done supporting a 1:2 compression, but that professional version would have losed all it's compression capabilities.

 

[deathkiller]

Because bigger is the file , more compression you need to match the max bit rate , so if you have to compress an hd video master of about 2 hour, you will never be able to do with am 1:12 ratio , because this would need a bit rate over the max bit rate used from the codec.

I did not specificate any bitrate when compresing the video, I did get a 120Mbit bitrate using Quantizer 0 wich means that I am using it as a lossless codec, the MPEG4 is not optimized to be used like that but even if the standar not suport it the implementations have it.

 

[iknowall]

I did not specificate any bitrate when compresing the video, I did get a 120Mbit bitrate using Quantizer 0 wich means that I am using it as a lossless codec, the MPEG4 is not optimized to be used like that but even if the standar not suport it the implementations have it.

Even using quantizer 0 you are not going to have no copmpression, because to have no compression you have to use an uncompressed codec.

And bigger is the file you encode, less will be the final bitrate.

Bit rate = compression ratio. Using less compression means using an higer bit rate

 

[hongcho]

Sony never intended to use those advanced codecs (MPEG-4 AVC and VC-1) on BD because of the patent income/fee issue. and the compatibility with existing equipment. They reluctantly agreed to include the advanced codecs when it was shown that they were indeed more efficient than MPEG-2 (you know, those fabulous codec researchers holding Ph.Ds can do wonders during those 10 years), and their BD capacity leader story got cut short by HD-DVD using the advanced codecs.

I am guessing that all initial BD software releases will be in MPEG-2.

BTW, the codec efficiency and the compression ratio do not always go hand in hand. An efficient codec, by definition, can reproduce the same quality with fewer number of bits.

Hong.

 

[PC-Engine]

Sony never intended to use those advanced codecs (MPEG-4 AVC and VC-1) on BD because of the patent income/fee issue. and the compatibility with existing equipment. They reluctantly agreed to include the advanced codecs when it was shown that they were indeed more efficient than MPEG-2 (you know, those fabulous codec researchers holding Ph.Ds can do wonders during those 10 years), and their BD capacity leader story got cut short by HD-DVD using the advanced codecs.

I am guessing that all initial BD software releases will be in MPEG-2.

BTW, the codec efficiency and the compression ratio do not always go hand in hand. An efficient codec, by definition, can reproduce the same quality with fewer number of bits.

Hong.

Thanks for that post Hong. The last two pages of "MPEG2 > MPEG4" nonsense was at least good for a laugh. I think somebody needs to read the AVS thread and educate himself.

 

[iknowall]

Thanks for that post Hong. The last two pages of "MPEG2 > MPEG4" nonsense was at least good for a laugh. I think somebody needs to read the AVS thread and educate himself.

Yeah you are right you that work in a post production studios and have years of expecience in the indusatrial video encoding can teach us how the real deal is .

Oh wait, you dont ?

This post make me laugh cause of it's nonsense. What make me laugh is you claim something right or wrong but you never had real word experience of what are you talking about.

Btw, if you have a valid argument, expose , if don't , just don't trash other people opinions, expecially if your opinion are based on therory and not of real world situation.

Hum

Sony never intended to use those advanced codecs (MPEG-4 AVC and VC-1) on BD because of the patent income/fee issue

Oh really ? that's strange because sony use mpeg4 codecs for a lot of things, even at professiona lever they use the mpeg4 sp codec, studio profile, for compressing a little bit the video on the hdcam sr format.

 

[PC-Engine]

Yeah you are right you that work in a post production studios and have years of expecience in the indusatrial video encoding can teach us how the real deal is .

Oh wait, you dont ?

Yeah and I'm sure you expect us to believe you..some anonymous FUD poster on the internet.

This post make me laugh cause of it's nonsense. What make me laugh is you claim something right or wrong but you never had real word experience of what are you talking about.

Btw, if you have a valid argument, expose , if don't , just don't trash other people opinions, expecially if your opinion are based on therory and not of real world situation.

I don't think you've established any positive credibility here to make your post worth more than BS.

25GB SL BR movies using MPEG2 from SONY...that's all you need to know.