[FFmpeg-devel] entropy coding in dvcpro

EVS Hardware Dpt hardware.evs
Tue Jan 6 14:33:27 CET 2009

Hello Roman,

There is an ambiguity in the spec. Indeed the sentence you mentioned in your
answer suggests that it is mandatory. But in the variable length coding
section of the same spec one can read: "When the values of all of the
remaining quantized coefficients are zero within a DCT block, the coding
process is ended by adding the EOB (end of block) code word of 0110b
immediately after the last code word." This last paragraph suggests that if
the last ac quantized coefficients is non-zero, an EOB code words is not

2009/1/5 Roman V. Shaposhnik <rvs at sun.com>

> On Wed, 2008-12-24 at 11:01 +0100, EVS Hardware Dpt wrote:
> > Hello,
> >
> > I was wondering whether the presence of EOB code is mandatory or optional
> if
> > the 63th AC coefficients is non-zero.
> My reading of the SPEC suggests that its mandatory:
> -------------------------------------------------------
> Code words for AC coefficients of B i, j, k, l shall be
> concatenated according to the order as shown in
> figure 27 and the last code word shall be EOB.
> -------------------------------------------------------
> Thanks,
> Roman.
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at mplayerhq.hu
> https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel

More information about the ffmpeg-devel mailing list