On 5 May 2016 at 10:06, Christophe Gisquet <christophe.gisq...@gmail.com> wrote:
> The slice prefix is 0 in the reference encoder and the decoder ignores it. > Writing 0 there seems like the best temporary solution. > > The padding could have contained uninitialized data, but reference VC2 > encoders put 0xFF there, hence the memset value. > > Overall this allows producing bistreams with no random data for use by > fate. > --- > libavcodec/vc2enc.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/libavcodec/vc2enc.c b/libavcodec/vc2enc.c > index 6d24552..bbbeaa0 100644 > --- a/libavcodec/vc2enc.c > +++ b/libavcodec/vc2enc.c > @@ -777,7 +777,10 @@ static int encode_hq_slice(AVCodecContext *avctx, > void *arg) > uint8_t quants[MAX_DWT_LEVELS][4]; > int p, level, orientation; > > + /* The reference decoder ignores it, and its typical length is 0 */ > + memset(put_bits_ptr(pb), 0, s->prefix_bytes); > skip_put_bytes(pb, s->prefix_bytes); > + > put_bits(pb, 8, quant_idx); > > /* Slice quantization (slice_quantizers() in the specs) */ > @@ -809,6 +812,8 @@ static int encode_hq_slice(AVCodecContext *avctx, void > *arg) > } > pb->buf[bytes_start] = pad_s; > flush_put_bits(pb); > + /* vc2-reference uses that padding that decodes to '0' coeffs */ > + memset(put_bits_ptr(pb), 0xFF, pad_c); > skip_put_bytes(pb, pad_c); > } > > -- > 2.8.1 > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel > Thanks a lot, pushed. I plan to merge the fate tests as well tomorrow or on Saturday when I'll have time to quickly fix bugs which appear on platforms I haven't tested the encoder on. Hopefully none, but you never know. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
