H.264 /Mpeg-4 AVC efficiency...Wow!

[CityK]

Having just read Doom9's latest codec shootout on the weekend, I got to fooling/messing around and made a bunch of really short TV captures using Huffyuv and then transcoded using some different codecs.

To give an example of how impressive AVC is going to be, consider the following:

131 frames (just over 4 sec), 704x480 clip, using the lossless Huffyuv compression codec results in a file size of 36,021,760 bytes (of which 35,059,588 bytes are video data, rest PCM audio, metadata etc..). Thats over 2.5x times video compression.

For mpeg-4 ASP, Xvid is my personal fav. Xvid file size: 5,918,720 bytes. Nice. 16% the size of the loseless Huffy encoded file.

Now for Mpeg-4 AVC, I used mpegable's codec, and the resultant file size: 1,214,464 bytes. Holy smokes! 3.3% of the Huffy!!

 

[timwhit]

How did it look?

 

[Jan Kivar]

And does it need a Cray to decode in real-time? :mrgrn:

Jan

 

[P5-133XL]

How did it look?

And does it need a Cray to decode in real-time? :mrgrn:

Jan

Those are the questions when dealing with a new decompression algorithum... and of course what is the compression ratio.

 

[sechs]

I'd also be curious as to whether compression took place in a reasonable period of time....

 

[blakerwry]

And compatibility with set top players...

 

[CityK]

Hi,

Sorry for the delay. My motherboard died monday morning.

Unfortunately I haven't had the opportunigy to play around some more (see above explanation). However, the AVC clips looked quite good - with the one capture that I was really comparing between the codecs, I actually prefered the AVC over the ASP (Xvid). The clip contained a lot of motion, so it was a good test in that respect. As for the encoding time - that was something that I was wondering about myself, but, absentmindedly, I forgot to take notice of how much actually elapsed. Subjectively, I don't recall there being much of a difference from the Xvid encodes, however, bear in mind that the clips were all in the 4-10s range...so even if it took 50% greater then the Xvid encode, its unlikely I would have attached much thought to it as generally kill the time arranging something on my desk etc. etc.

Playback of the AVC, on my aged XP1600, wasn't quite fluid, but it was probably in ~ 80% of 30fps...and, of course, CPU usage was pegged at 100%. I don't think modern processors would have much trouble handling it though.

As for standalones, the Doom9 article mentions that AVC capable players are on indeed on tap for 2005.

 

[CityK]

That should have been Tuesday morning...I had monday off because of the new years holiday (markets closed)....I keep thinking today's Wed.

 

[ddrueding]

Following up on this. I currently use XviD for my encoding, but have plenty of CPU power to throw around (who doesn't these days). What size savings could I expect transcoding to h.264? The files are currently 2GB each (about 720x480 with 6 channel audio) and if I could get a savings of even 25%, that would be 300GB.

If it does sound like a good idea, what are the software tools that would make my life easier?

TIA