[FFmpeg-devel] [PATCH] HAM6/HAM8 support for IFF demuxer/decoder

[Michael Niedermayer]

On Wed, May 05, 2010 at 05:28:07PM +0200, Sebastian Vater wrote:
> Sebastian Vater a ?crit :
> > Because of backward compatibility I have changed it to append the
> > extradata struct after the palette (because in the original version, the
> > palette data was always at 0).
> >   
> 
> I just changed the minimum size of extradata to 256*3 (768 bytes). This
> will allow the new decoder to detect old libavformat/iff.c which doesn't
> set a large palette.
> 
> The palette data from old demuxer was never larger than 256*3 bytes (8
> bit palette, RGB each).
> 

[...]

> @@ -152,9 +157,15 @@ static int iff_read_header(AVFormatContext *s,
>              st->codec->channels = (get_be32(pb) < 6) ? 1 : 2;
>              break;
>  
> +        case ID_CAMG:
> +            if (data_size < 4)
> +                return AVERROR_INVALIDDATA;
> +            screenmode                = get_be32(pb);
> +            break;

can this value change from frame to frame or is it constant throghout a movie?
if it can change then it must be stored in AVPacket.data



> +
>          case ID_CMAP:
> -            st->codec->extradata_size = data_size;
> -            st->codec->extradata      = av_malloc(data_size);
> +            st->codec->extradata_size = data_size + IFF_EXTRA_CONTEXT_SIZE;
> +            st->codec->extradata      = av_malloc(data_size + IFF_EXTRA_CONTEXT_SIZE);
>              if (!st->codec->extradata)
>                  return AVERROR(ENOMEM);
>              if (get_buffer(pb, st->codec->extradata, data_size) < 0)
> @@ -169,12 +180,15 @@ static int iff_read_header(AVFormatContext *s,
>              st->codec->height                = get_be16(pb);
>              url_fskip(pb, 4); // x, y offset



>              st->codec->bits_per_coded_sample = get_byte(pb);
> -            if (data_size >= 11) {
> -                url_fskip(pb, 1); // masking
> +            if (data_size >= 10)
> +                masking                      = get_byte(pb);
> +            if (data_size >= 11)
>                  compression                  = get_byte(pb);
> +            if (data_size >= 14) {
> +                url_fskip(pb, 1); // padding
> +                transparency                 = get_be16(pb);
>              }

it appears to me that the whole above should be stored in extradata as is
or maybe even the whole BMHD


[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

If you think the mosad wants you dead since a long time then you are either
wrong or dead since a long time.
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