[FFmpeg-devel] [PATCH 2/3] ac3enc: shift coefficients to 24-bit following MDCT rather than using an exponent offset.
Wed Mar 9 23:41:34 CET 2011
Justin Ruggles <justin.ruggles at gmail.com> writes:
> On 03/09/2011 04:48 PM, M?ns Rullg?rd wrote:
>> Justin Ruggles <justin.ruggles at gmail.com> writes:
>>> This makes channel coupling more accurate, increasing quality for stereo
>>> content. It also simplifies exponent extraction and mantissa quantization
>>> by no longer needing to apply an offset to the exponents.
>>> libavcodec/ac3enc.c | 13 ++++++-------
>>> libavcodec/ac3enc_fixed.c | 42 ++++++++++++++++++++++++++++++++++--------
>>> tests/ref/acodec/ac3_fixed | 2 +-
>>> 3 files changed, 41 insertions(+), 16 deletions(-)
>> Looks OK.
> Please hold off on applying this patch and #3 to git.ffmpeg.org.
> I have another patch which will only need right shifting for the
> coefficient scaling and gets better quality (and likely better speed,
> but I haven't done benchmarks yet).
OK, we await your new patch with anticipation.
mans at mansr.com
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