diff options
| author | Maxim Poliakovski <max_pole@gmx.de> | 2014-02-08 22:27:51 +0100 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2014-02-08 23:09:57 +0100 |
| commit | 3f826039ddccdd7840cdf982a1a61cb11121a5a9 (patch) | |
| tree | 4beb8eaf83c27deb000af8c4289a440bc82dbbe8 /libavcodec/g2meet.c | |
| parent | cb2162adba4041951c987f9f365957e067b28a97 (diff) | |
| download | ffmpeg-3f826039ddccdd7840cdf982a1a61cb11121a5a9.tar.gz | |
g2meet: factor out chunk seeking
This version requires fewer code and is safer.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/g2meet.c')
| -rw-r--r-- | libavcodec/g2meet.c | 21 |
1 files changed, 8 insertions, 13 deletions
diff --git a/libavcodec/g2meet.c b/libavcodec/g2meet.c index b982eabccd..c2fcedaedf 100644 --- a/libavcodec/g2meet.c +++ b/libavcodec/g2meet.c @@ -646,7 +646,7 @@ static int g2m_decode_frame(AVCodecContext *avctx, void *data, int magic; int got_header = 0; uint32_t chunk_size; - int chunk_type; + int chunk_type, chunk_start; int i; int ret; @@ -672,8 +672,9 @@ static int g2m_decode_frame(AVCodecContext *avctx, void *data, } while (bytestream2_get_bytes_left(&bc) > 5) { - chunk_size = bytestream2_get_le32(&bc) - 1; - chunk_type = bytestream2_get_byte(&bc); + chunk_size = bytestream2_get_le32(&bc) - 1; + chunk_type = bytestream2_get_byte(&bc); + chunk_start = bytestream2_tell(&bc); if (chunk_size > bytestream2_get_bytes_left(&bc)) { av_log(avctx, AV_LOG_ERROR, "Invalid chunk size %d type %02X\n", chunk_size, chunk_type); @@ -722,8 +723,6 @@ static int g2m_decode_frame(AVCodecContext *avctx, void *data, c->tiles_x = (c->width + c->tile_width - 1) / c->tile_width; c->tiles_y = (c->height + c->tile_height - 1) / c->tile_height; c->bpp = bytestream2_get_byte(&bc); - chunk_size -= 21; - bytestream2_skip(&bc, chunk_size); if (g2m_init_buffers(c)) { ret = AVERROR(ENOMEM); goto header_fail; @@ -734,7 +733,6 @@ static int g2m_decode_frame(AVCodecContext *avctx, void *data, if (!c->tiles_x || !c->tiles_y) { av_log(avctx, AV_LOG_WARNING, "No display info - skipping tile\n"); - bytestream2_skip(&bc, bytestream2_get_bytes_left(&bc)); break; } if (chunk_size < 2) { @@ -750,7 +748,6 @@ static int g2m_decode_frame(AVCodecContext *avctx, void *data, c->tile_x, c->tile_y, c->tiles_x, c->tiles_y); break; } - chunk_size -= 2; ret = 0; switch (c->compression) { case COMPR_EPIC_J_B: @@ -760,13 +757,12 @@ static int g2m_decode_frame(AVCodecContext *avctx, void *data, case COMPR_KEMPF_J_B: ret = kempf_decode_tile(c, c->tile_x, c->tile_y, buf + bytestream2_tell(&bc), - chunk_size); + chunk_size - 2); break; } if (ret && c->framebuf) av_log(avctx, AV_LOG_ERROR, "Error decoding tile %d,%d\n", c->tile_x, c->tile_y); - bytestream2_skip(&bc, chunk_size); break; case CURSOR_POS: if (chunk_size < 5) { @@ -776,7 +772,6 @@ static int g2m_decode_frame(AVCodecContext *avctx, void *data, } c->cursor_x = bytestream2_get_be16(&bc); c->cursor_y = bytestream2_get_be16(&bc); - bytestream2_skip(&bc, chunk_size - 4); break; case CURSOR_SHAPE: if (chunk_size < 8) { @@ -787,17 +782,17 @@ static int g2m_decode_frame(AVCodecContext *avctx, void *data, bytestream2_init(&tbc, buf + bytestream2_tell(&bc), chunk_size - 4); g2m_load_cursor(avctx, c, &tbc); - bytestream2_skip(&bc, chunk_size); break; case CHUNK_CC: case CHUNK_CD: - bytestream2_skip(&bc, chunk_size); break; default: av_log(avctx, AV_LOG_WARNING, "Skipping chunk type %02X\n", chunk_type); - bytestream2_skip(&bc, chunk_size); } + + /* navigate to next chunk */ + bytestream2_skip(&bc, chunk_start + chunk_size - bytestream2_tell(&bc)); } if (got_header) c->got_header = 1; |