[FFmpeg-devel] Implementation of Huffman codes for DCA encoder

Даниил Чередник dan.cherednik at gmail.com
Sun Jan 15 19:34:20 EET 2017


On Sun, Jan 15, 2017 at 6:58 PM, Paul B Mahol <onemda at gmail.com> wrote:

> On 1/15/17, Daniil CHerednik <dan.cherednik at gmail.com> wrote:
> > Hi.
> > Is there any issue in this patch?
>
> Do you plan to work more on this encoder?
>
Yes I do.

>
> Please do not top post.
>
Ok, sorry.

>
> >
> > On Sun, Jan 8, 2017 at 1:22 AM, Daniil CHerednik <
> dan.cherednik at gmail.com>
> > wrote:
> >
> >> With real music and 256k bitrate encoding (the source was 44100, 16bit
> >> stereo) I got:
> >> Without Huffman: Best PSNR is  31.77 for shift 0
> >> With: Best PSNR is  37.45 for shift 0
> >>
> >> Current implementation of DCA encoder has minimal set of DTS features
> (no
> >> ADPCM, no VQ, fixed amount of transmitted subbands, no transient
> control,
> >> etc). So distortion is quite audible. Current set of patches introduces
> >> Huffman encoding for quantized audio data which is equivalent of
> >> increasing
> >> bitrate for 10-20%. Also bitstream allows to use Huffman for scale
> factor
> >> indexes, and some other data. I am working on it too.
> >>
> >> I have attached new split set of patches.
> >>
> >> On Sat, Jan 7, 2017 at 11:50 PM, Carl Eugen Hoyos <ceffmpeg at gmail.com>
> >> wrote:
> >>
> >>> 2017-01-07 20:39 GMT+01:00 Rostislav Pehlivanov <atomnuker at gmail.com>:
> >>> > On 7 January 2017 at 16:11, Carl Eugen Hoyos <ceffmpeg at gmail.com>
> >>> wrote:
> >>> >
> >>> >> 2017-01-07 16:00 GMT+01:00 Daniil CHerednik <
> dan.cherednik at gmail.com>:
> >>> >>
> >>> >> > Currently I am working on improvement quality of DTS encoder.
> >>> Following
> >>> >> > patches introduce Huffman coding.
> >>> >>
> >>> >> Is the quality improvement so obvious that no further tests are
> >>> necessary?
> >>> >> (Does psnr improve measurably?)
> >>> >>
> >>> > PSNR is pretty much useless for audio.
> >>>
> >>> > The ear's the only metric which works.
> >>>
> >>> Not everybody's;-))
> >>>
> >>> > From the 2 samples he posted I can tell there's a big difference, and
> >>> the
> >>> > encoder isn't very good right now and the patch definitely helps.
> >>>
> >>> Thank you!
> >>>
> >>> Carl Eugen
> >>> _______________________________________________
> >>> ffmpeg-devel mailing list
> >>> ffmpeg-devel at ffmpeg.org
> >>> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> >>>
> >>
> >>
> >>
> >> --
> >> Daniil Cherednik
> >>
> >
> >
> >
> > --
> > Daniil Cherednik
> > _______________________________________________
> > ffmpeg-devel mailing list
> > ffmpeg-devel at ffmpeg.org
> > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> >
> _______________________________________________
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>



-- 
Daniil Cherednik


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