[FFmpeg-devel] [PATCH 2/2] lavf/swfdec: support DefineBitsLossless{, 2} tag.

[Paul B Mahol]

On 10/12/12, Clement Boesch <ubitux at gmail.com> wrote:
> ---
>  libavformat/swfdec.c | 114
> +++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 114 insertions(+)
>
> diff --git a/libavformat/swfdec.c b/libavformat/swfdec.c
> index 48a2156..3fe31d4 100644
> --- a/libavformat/swfdec.c
> +++ b/libavformat/swfdec.c
> @@ -20,6 +20,7 @@
>   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
> USA
>   */
>
> +#include "libavutil/avassert.h"
>  #include "libavutil/intreadwrite.h"
>  #include "swf.h"
>
> @@ -253,6 +254,119 @@ static int swf_read_packet(AVFormatContext *s,
> AVPacket *pkt)
>                      return pkt->size;
>                  }
>              }
> +        } else if (tag == TAG_DEFINEBITSLOSSLESS || tag ==
> TAG_DEFINEBITSLOSSLESS2) {
> +#if CONFIG_ZLIB
> +            long out_len;
> +            uint8_t *buf, *zbuf, *pal;
> +            uint32_t colormap[AVPALETTE_COUNT] = {0};
> +            const int alpha_bmp = tag == TAG_DEFINEBITSLOSSLESS2;
> +            const int colormapbpp = 3 + alpha_bmp;
> +            int linesize, colormapsize = 0;
> +
> +            const int ch_id   = avio_rl16(pb);
> +            const int bmp_fmt = avio_r8(pb);
> +            const int width   = avio_rl16(pb);
> +            const int height  = avio_rl16(pb);
> +
> +            len -= 2+1+2+2;
> +
> +            switch (bmp_fmt) {
> +            case 3: // PAL-8
> +                linesize = width;
> +                colormapsize = avio_r8(pb) + 1;
> +                len--;
> +                break;
> +            case 4: // RGB15
> +                linesize = width * 2;
> +                break;
> +            case 5: // RGB24 (0RGB)
> +                linesize = width * 4;
> +                break;
> +            default:
> +                av_log(s, AV_LOG_ERROR, "invalid bitmap format %d,
> skipped\n", bmp_fmt);
> +                goto bitmap_end_skip;
> +            }
> +
> +            linesize = FFALIGN(linesize, 4);
> +            out_len = colormapsize * colormapbpp + linesize * height;
> +
> +            av_dlog(s, "bitmap: ch=%d fmt=%d %dx%d (linesize=%d)
> len=%d->%ld pal=%d\n",
> +                    ch_id, bmp_fmt, width, height, linesize, len, out_len,
> colormapsize);
> +
> +            zbuf = av_malloc(len);
> +            buf  = av_malloc(out_len);
> +            if (!zbuf || !buf) {
> +                res = AVERROR(ENOMEM);
> +                goto bitmap_end;
> +            }
> +
> +            avio_read(pb, zbuf, len);
> +            if ((res = uncompress(buf, &out_len, zbuf, len)) != Z_OK) {
> +                av_log(s, AV_LOG_WARNING, "Failed to uncompress one
> bitmap\n");
> +                goto bitmap_end_skip;
> +            }
> +
> +            for (i = 0; i < s->nb_streams; i++) {
> +                st = s->streams[i];
> +                if (st->codec->codec_id == AV_CODEC_ID_RAWVIDEO && st->id
> == -3)
> +                    break;
> +            }
> +            if (i == s->nb_streams) {
> +                vst = avformat_new_stream(s, NULL);
> +                if (!vst) {
> +                    res = AVERROR(ENOMEM);
> +                    goto bitmap_end;
> +                }
> +                vst->id = -3; /* -3 to avoid clash with video stream and
> audio stream */
> +                vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
> +                vst->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
> +                avpriv_set_pts_info(vst, 64, 256, swf->frame_rate);
> +                st = vst;
> +            }
> +            st->codec->width  = width;
> +            st->codec->height = height;
> +
> +            if ((res = av_new_packet(pkt, out_len - colormapsize *
> colormapbpp)) < 0)
> +                goto bitmap_end;
> +            pkt->pos = pos;
> +            pkt->stream_index = st->index;
> +
> +            switch (bmp_fmt) {
> +            case 3:
> +                st->codec->pix_fmt = AV_PIX_FMT_PAL8;
> +                for (i = 0; i < colormapsize; i++)
> +                    if (alpha_bmp)  colormap[i] = buf[3]<<24 | AV_RB24(buf
> + 4*i);
> +                    else            colormap[i] = 0xffU <<24 | AV_RB24(buf
> + 3*i);
> +                pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE,
> AVPALETTE_SIZE);
> +                if (!pal) {
> +                    res = AVERROR(ENOMEM);
> +                    goto bitmap_end;
> +                }
> +                memcpy(pal, colormap, AVPALETTE_SIZE);
> +                break;
> +            case 4:
> +                st->codec->pix_fmt = AV_PIX_FMT_RGB555;
> +                break;
> +            case 5:
> +                st->codec->pix_fmt = alpha_bmp ? AV_PIX_FMT_ARGB :
> AV_PIX_FMT_0RGB;
> +                break;
> +            default:
> +                av_assert0(0);
> +            }
> +            memcpy(pkt->data, buf + colormapsize*colormapbpp, linesize *
> height);
> +
> +            res = pkt->size;
> +
> +bitmap_end:
> +            av_freep(&zbuf);
> +            av_freep(&buf);
> +            return res;
> +bitmap_end_skip:
> +            av_freep(&zbuf);
> +            av_freep(&buf);

Freeing random stuff is bad idea.
> +#else
> +            av_log(s, AV_LOG_ERROR, "this file requires zlib support
> compiled in\n");
> +#endif
>          } else if (tag == TAG_SOUNDSTREAMBLOCK) {
>              for (i = 0; i < s->nb_streams; i++) {
>                  st = s->streams[i];
> --
> 1.7.12.2
>
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