diff options
| -rw-r--r-- | libavcodec/mpegaudiodec_template.c | 29 |
1 files changed, 15 insertions, 14 deletions
diff --git a/libavcodec/mpegaudiodec_template.c b/libavcodec/mpegaudiodec_template.c index 2518387162..9bfba6f221 100644 --- a/libavcodec/mpegaudiodec_template.c +++ b/libavcodec/mpegaudiodec_template.c @@ -70,6 +70,7 @@ typedef struct MPADecodeContext { MPA_DECODE_HEADER uint8_t last_buf[LAST_BUF_SIZE]; int last_buf_size; + int extrasize; /* next header (used in free format parsing) */ uint32_t free_format_next_header; GetBitContext gb; @@ -798,9 +799,10 @@ static void exponents_from_scale_factors(MPADecodeContext *s, GranuleDef *g, static void switch_buffer(MPADecodeContext *s, int *pos, int *end_pos, int *end_pos2) { - if (s->in_gb.buffer && *pos >= s->gb.size_in_bits) { + if (s->in_gb.buffer && *pos >= s->gb.size_in_bits - s->extrasize * 8) { s->gb = s->in_gb; s->in_gb.buffer = NULL; + s->extrasize = 0; assert((get_bits_count(&s->gb) & 7) == 0); skip_bits_long(&s->gb, *pos - *end_pos); *end_pos2 = @@ -832,7 +834,7 @@ static int huffman_decode(MPADecodeContext *s, GranuleDef *g, int i; int last_pos, bits_left; VLC *vlc; - int end_pos = FFMIN(end_pos2, s->gb.size_in_bits); + int end_pos = FFMIN(end_pos2, s->gb.size_in_bits - s->extrasize * 8); /* low frequencies (called big values) */ s_index = 0; @@ -1354,19 +1356,16 @@ static int mp_decode_layer3(MPADecodeContext *s) if (!s->adu_mode) { int skip; const uint8_t *ptr = s->gb.buffer + (get_bits_count(&s->gb)>>3); - int extrasize = av_clip(get_bits_left(&s->gb) >> 3, 0, - FFMAX(0, LAST_BUF_SIZE - s->last_buf_size)); + s->extrasize = av_clip((get_bits_left(&s->gb) >> 3) - s->extrasize, 0, + FFMAX(0, LAST_BUF_SIZE - s->last_buf_size)); assert((get_bits_count(&s->gb) & 7) == 0); /* now we get bits from the main_data_begin offset */ ff_dlog(s->avctx, "seekback:%d, lastbuf:%d\n", main_data_begin, s->last_buf_size); - memcpy(s->last_buf + s->last_buf_size, ptr, extrasize); + memcpy(s->last_buf + s->last_buf_size, ptr, s->extrasize); s->in_gb = s->gb; - init_get_bits(&s->gb, s->last_buf, s->last_buf_size*8); -#if !UNCHECKED_BITSTREAM_READER - s->gb.size_in_bits_plus8 += extrasize * 8; -#endif + init_get_bits(&s->gb, s->last_buf, (s->last_buf_size + s->extrasize) * 8); s->last_buf_size <<= 3; for (gr = 0; gr < nb_granules && (s->last_buf_size >> 3) < main_data_begin; gr++) { for (ch = 0; ch < s->nb_channels; ch++) { @@ -1377,15 +1376,17 @@ static int mp_decode_layer3(MPADecodeContext *s) } } skip = s->last_buf_size - 8 * main_data_begin; - if (skip >= s->gb.size_in_bits && s->in_gb.buffer) { - skip_bits_long(&s->in_gb, skip - s->gb.size_in_bits); + if (skip >= s->gb.size_in_bits - s->extrasize * 8 && s->in_gb.buffer) { + skip_bits_long(&s->in_gb, skip - s->gb.size_in_bits + s->extrasize * 8); s->gb = s->in_gb; s->in_gb.buffer = NULL; + s->extrasize = 0; } else { skip_bits_long(&s->gb, skip); } } else { gr = 0; + s->extrasize = 0; } for (; gr < nb_granules; gr++) { @@ -1553,7 +1554,7 @@ static int mp_decode_frame(MPADecodeContext *s, OUT_INT **samples, s->last_buf_size=0; if (s->in_gb.buffer) { align_get_bits(&s->gb); - i = get_bits_left(&s->gb)>>3; + i = (get_bits_left(&s->gb) >> 3) - s->extrasize; if (i >= 0 && i <= BACKSTEP_SIZE) { memmove(s->last_buf, s->gb.buffer + (get_bits_count(&s->gb)>>3), i); s->last_buf_size=i; @@ -1561,12 +1562,12 @@ static int mp_decode_frame(MPADecodeContext *s, OUT_INT **samples, av_log(s->avctx, AV_LOG_ERROR, "invalid old backstep %d\n", i); s->gb = s->in_gb; s->in_gb.buffer = NULL; + s->extrasize = 0; } align_get_bits(&s->gb); assert((get_bits_count(&s->gb) & 7) == 0); - i = get_bits_left(&s->gb) >> 3; - + i = (get_bits_left(&s->gb) >> 3) - s->extrasize; if (i < 0 || i > BACKSTEP_SIZE || nb_frames < 0) { if (i < 0) av_log(s->avctx, AV_LOG_ERROR, "invalid new backstep %d\n", i); |