Re: [rtcweb] New VP8 vs H.264 tests uploaded

Ok, thanks for very clear explanation :).

Luca

On Thu, Apr 4, 2013 at 4:30 PM, Harald Alvestrand <harald@alvestrand.no> wrote:
> On 04/04/2013 03:59 PM, Luca De Cicco wrote:
>>
>> Why did you use baseline instead of mainline or highline for x264? It
>> should be better to compare
>> vp8 at least with the mainline profile.
>
> Better in what sense?
>
> This is the discussion of the MTI for RTCWEB; the proponents of H.264 as MTI
> have proposed:
>
>    The core of the proposal is that H.264 Constrained Baseline Profile
>    Level 1.2 MUST be supported as Mandatory To Implement video codec.
>    To enable higher quality for devices capable of it, support for H.264
>    Constrained High Profile Level 1.3, extended to support 720p
>    resolution at 30 Hz framerate is RECOMMENDED.
>
> (draft-burman-rtcweb-h264-proposal-01.txt section 1)
>
> The scripts we have published is trying to compare what the H.264 proponents
> have proposed for MTI with what the VP8 proponents have proposed for MTI.
>
>
>>
>> Cheers,
>> Luca
>>
>> On Thu, Apr 4, 2013 at 3:30 PM, Harald Alvestrand <harald@alvestrand.no>
>> wrote:
>>>
>>> On 04/04/2013 10:53 AM, Sergio Garcia Murillo wrote:
>>>
>>> Hi Adrian,
>>>
>>> Could you explain how the encoding parametrization is comparable?
>>>
>>> x264 --nal-hrd cbr --vbv-maxrate ${rate} --vbv-bufsize ${rate} \
>>>        --vbv-init 0.8 --bitrate ${rate} --fps ${frame_rate} \
>>>        --profile baseline --no-scenecut --keyint infinite --preset
>>> veryslow \
>>>        --input-res ${width}x${height} \
>>>        --tune psnr \
>>>        -o ./encoded_clips/h264/${clip_stem}_${rate}kbps.mkv ${filename} \
>>>        2> ./logs/h264/${clip_stem}_${rate}kbps.txt
>>>
>>> vs:
>>>
>>>   ./bin/vpxenc --lag-in-frames=0 --target-bitrate=${rate}
>>> --kf-min-dist=3000
>>> \
>>>        --kf-max-dist=3000 --cpu-used=0 --fps=${frame_rate}/1
>>> --static-thresh=0 \
>>>        --token-parts=1 --drop-frame=0 --end-usage=cbr --min-q=2
>>> --max-q=56 \
>>>        --undershoot-pct=100 --overshoot-pct=15 --buf-sz=1000 \
>>>        --buf-initial-sz=800 --buf-optimal-sz=1000 --max-intra-rate=1200 \
>>>        --resize-allowed=0 --drop-frame=0 --passes=1 --good
>>> --noise-sensitivity=0 \
>>>        -w ${width} -h ${height} ${filename} --codec=vp8 \
>>>        -o ./encoded_clips/vp8/${clip_stem}_${rate}kbps.webm \
>>>        &>./logs/vp8/${clip_stem}_${rate}kbps.txt
>>>
>>>
>>> Both have the same target bitrate and the same resolution, and neither
>>> generates periodic keyframes.
>>>
>>> Apart from that, I think they are comparable by virtue of being the
>>> parameters that were recommended for this test by people who like this
>>> particular codec implementation.
>>>
>>> Was there any specific parameter or parameter set you were wondering
>>> about?
>>>
>>>
>>>
>>>
>>> Best regards
>>> Sergio
>>>
>>> El 03/04/2013 18:20, Adrian Grange escribió:
>>>
>>> We have uploaded a new set of test results comparing VP8 to H.264. This
>>> latest set contains fixes for some of the problems in the previous set.
>>> We
>>> would like to extend our thanks to those who made suggestions as to how
>>> we
>>> could improve our methodology and encourage suggestions as to how we can
>>> make further improvements.
>>>
>>> In these tests we run x264 with the "veryslow" preset and VP8 with the
>>> "good, speed 0" setting in an attempt to produce comparable results.
>>>
>>> An overview of our results is available as follows:
>>>
>>> - A Quality comparison (psnr):
>>> http://downloads.webmproject.org/ietf_tests/vp8_vs_h264_quality.html
>>>
>>> - An Encode Speed comparison:
>>> http://downloads.webmproject.org/ietf_tests/vp8_vs_h264_speed.html
>>>
>>> - A comparison of the aggregate time required to decode all of the clips
>>> in
>>> the test:
>>> http://downloads.webmproject.org/ietf_tests/vp8vsh264-decodetime.txt
>>>
>>> All of our test scripts can either be downloaded from:
>>> http://downloads.webmproject.org/ietf_tests/vp8_vs_h264.tar.xz
>>> or checked out of our git/gerrit repository:
>>> git clone http://git.chromium.org/webm/vpx_codec_comparison.git
>>>
>>> The file README.txt, contained within, presents details of how to build
>>> and
>>> run the tests.
>>>
>>> The compressed video files--the output from the quality tests--can also
>>> be
>>> downloaded:
>>>
>>> VP8:
>>> http://downloads.webmproject.org/ietf_tests/vp8_videos/index.html
>>>
>>> H.264:
>>> http://downloads.webmproject.org/ietf_tests/h264_videos/index.html
>>>
>>> Adrian Grange
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> rtcweb mailing list
>>> rtcweb@ietf.org
>>> https://www.ietf.org/mailman/listinfo/rtcweb
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> rtcweb mailing list
>>> rtcweb@ietf.org
>>> https://www.ietf.org/mailman/listinfo/rtcweb
>>>
>>>
>>>
>>> _______________________________________________
>>> rtcweb mailing list
>>> rtcweb@ietf.org
>>> https://www.ietf.org/mailman/listinfo/rtcweb
>>>
>