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

[Clément Bœsch]

---
 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);
+#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