[x264-devel] Re: [Mp4-tech] CALL FOR MPEG4-AVC/H.264 CODECS (fwd)
Alexander Izvorski
aizvorski at gmail.com
Mon Aug 29 14:17:27 CEST 2005
here are my two cents...
first a few hints:
specify the real fps explicitly, otherwise ratecontrol results may be bad.
don't use interlaced footage, interlaced encoding is not supported and
the results on interlaced footage will not be representative of the
quality of the encoder. if necessary, deinterlace first (for example,
using mencoder's -vf kerndeint).
denoise first (for example, using mencoder's -vf hqdn3d). commercial
encoders often include this, x264 relies on proper preprocessing.
each of the variants will (may) be lower quality. most are also
faster, sometimes a lot faster. it depends on what you mean by
"balanced" ;)
and finally the settings:
** best **
x264
--bitrate <bitrate>
--fps <fps>
--me esa
--merange 32
--subme 6
--ref 16
--analyse all
--8x8dct
--direct temporal
--bframes 2
--weightb
--b-pyramid
--cqm jvt
--progress
run three passes, --pass 1, --pass 2 and --pass 3
variants:
* replace --me esa with --me umh
* replace --ref 16 with --ref 4
* replace --cqm jvt with --cqm flat
** medium or "balanced" **
x264
--bitrate <bitrate>
--fps <fps>
--me umh
--merange 16
--subme 5
--ref 2
--analyse all
--8x8dct
--direct temporal
--bframes 2
--weightb
--b-pyramid
--cqm jvt
--progress
run two passes, --pass 1 and --pass 2
variants:
* replace --me umh with --me hex
* replace --subme 5 with --subme 3
* replace --ref 2 with --ref 1
* replace --cqm jvt with --cqm flat
** fast **
x264
--bitrate <bitrate>
--fps <fps>
--me dia
--merange 16
--subme 1
--ref 1
--analyse "p8x8,b8x8,i8x8,i4x4"
--direct temporal
--bframes 0
--no-cabac
--cqm flat
run once only
variants:
* remove --no-cabac (slower)
* replace --analyse "p8x8,b8x8,i8x8,i4x4" with --analyse none
* add --8x8dct (slower)
* replace --cqm flat with --cqm jvt
i believe that as shown (but without the variants) the above conform
to high, main and baseline profile respectively.
i don't remember if the bug which makes endoing results depend on
--progress is fixed, hence i'm including that.
-Alex
On 8/29/05, Tuukka Toivonen <tuukkat at ee.oulu.fi> wrote:
> I thought it might be nice to forward this message here too.
>
> I believe these people are aware of x264, but might not know
> the best encoding options.
>
> According to my experiments, the best safe encoding options are
>
> --bframes 3
> --no-b-adapt
> --b-pyramid
> --ref 14
> --pbratio 1.5
> --analyse all
> --direct temporal
> --me 3
> --merange 24
> --subme 6
> --8x8dct
>
> - "--direct spatial" would give higher performance in PSNR,
> but I'm not sure if it is usable, so I wouldn't recommend
> using it yet. There have been some fixes in x264, but
> I wasn't able to verify if they fixed the problem as
> I haven't been able to decode .264 into raw yuv with
> recent Mencoder cvs versions :(
> - Larger "--ref" might be slightly better but possibly with
> lesser compatibility
> - I don't have yet recommendations for "balanced" (ie. faster)
> coding options.
> - I haven't mailed the people below (maybe some developer
> would like to do it--it would be great to have an independent
> comparison of x264 to other encoders)
>
> ---------- Forwarded message ----------
> Date: Sun, 28 Aug 2005 02:46:40 +0400
> From: Dmitriy Vatolin <dmitriy at graphics.cs.msu.ru>
> To: mp4-tech at lists.mpegif.org
> Subject: [Mp4-tech] CALL FOR MPEG4-AVC/H.264 CODECS
>
> Hello!
>
> Please, forward this information to codecs developers!
>
> ================================================================
> CALL FOR MPEG4-AVC/H.264 CODECS
> Second Annual H.264 video codec comparison
> ================================================================
>
> For people, who make real research in field of high-end video compression
>
> Important Dates
> ---------------
>
> * September, 10 preliminary registration and settling of all formal issues
> * September, 20 deadline of codec receipt with required presets
> * September, 25 notification of codecs acceptance for tests notification
>
>
> Enhancements from Previous H.264/AVC Comparison
> -----------------------------------------------
>
> * Measuring will be performed with extended metrics set: PSNR, SSIM, VQM
> * Two codec presets will be compared: Maximum quality, Balanced (speed)
> * For each preset both speed and quality will be measured
>
>
> Codec Requirements
> ------------------
>
> * Codec should be H.264/AVC Main Profile codec
> * Codec should allow to set arbitrary bitrate of resulted sequence
> * 3 variants of codec interface are possible:
> * Console codec version (with batch processing support H bitrate and file names must be assigned from command line
> * Video for Windows Codec with correct state saving (batch processing support)
> * Direct Show filter. In this case software for batch processing should be provided
> * Codec should open and save *.yuv or *.avi (YUV colorspace) files
> * Result video sequences should be opened with standard methods
>
>
> Comparison Rules
> ----------------
>
> * All measurements will be produced by MSU Video Quality Measurement
> Tool( http://www.compression.ru/video/quality_measure/video_measurement_tool_en.html )
> * Codec options for Maximum quality and Balanced presets should be provided by codec authors. If these options won"tnot be provided, default options will be used
> * Verification of comparison results is possible for codec authors before comparison publication
> * Codec authors can delete all information about their codec from comparison document. In this case comparison authors can mention about this codec in public document without any received results
>
> See Previous H.264/AVC comparison for other rules and details.
>
>
> Useful Links
> ------------
>
> * Previous H.264/AVC comparison
> http://www.compression.ru/video/codec_comparison/mpeg-4_avc_h264_en.html
> * MPEG-4 SP/ASP comparison
> http://www.compression.ru/video/codec_comparison/mpeg-4_en.html
> * Lossless codecs comparison
> http://www.compression.ru/video/codec_comparison/lossless_codecs_en.html
>
>
> Contact info
> ------------
>
> Please contact us video at graphics.cs.msu.ru
>
> ================================================================
>
> --
> Best regards,
> Dmitriy mailto:dmitriy at graphics.cs.msu.ru
>
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>
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