diff --git a/libavcodec/dca_parser.c b/libavcodec/dca_parser.c index bde7dfe885..0b09ba5000 100644 --- a/libavcodec/dca_parser.c +++ b/libavcodec/dca_parser.c @@ -47,6 +47,14 @@ typedef struct DCAParseContext { #define CORE_MARKER(state) ((state >> 16) & 0xFFFFFFFF) #define EXSS_MARKER(state) (state & 0xFFFFFFFF) +#define STATE_LE(state) (((state & 0xFF00FF00) >> 8) | ((state & 0x00FF00FF) << 8)) +#define STATE_14(state) (((state & 0x3FFF0000) >> 8) | ((state & 0x00003FFF) >> 6)) + +#define CORE_FRAMESIZE(state) (((state >> 4) & 0x3FFF) + 1) +#define EXSS_FRAMESIZE(state) ((state & 0x2000000000) ? \ + ((state >> 5) & 0xFFFFF) + 1 : \ + ((state >> 13) & 0x0FFFF) + 1) + /** * Find the end of the current frame in the bitstream. * @return the position of the first byte of the next frame, or -1 @@ -54,12 +62,13 @@ typedef struct DCAParseContext { static int dca_find_frame_end(DCAParseContext *pc1, const uint8_t *buf, int buf_size) { - int start_found, i; + int start_found, size, i; uint64_t state; ParseContext *pc = &pc1->pc; start_found = pc->frame_start_found; state = pc->state64; + size = pc1->size; i = 0; if (!start_found) { @@ -80,15 +89,75 @@ static int dca_find_frame_end(DCAParseContext *pc1, const uint8_t *buf, } } } + if (start_found) { for (; i < buf_size; i++) { - pc1->size++; + size++; state = (state << 8) | buf[i]; + + if (start_found == 1) { + switch (pc1->lastmarker) { + case DCA_SYNCWORD_CORE_BE: + if (size == 2) { + pc1->framesize = CORE_FRAMESIZE(state); + start_found = 2; + } + break; + case DCA_SYNCWORD_CORE_LE: + if (size == 2) { + pc1->framesize = CORE_FRAMESIZE(STATE_LE(state)); + start_found = 2; + } + break; + case DCA_SYNCWORD_CORE_14B_BE: + if (size == 4) { + pc1->framesize = CORE_FRAMESIZE(STATE_14(state)) * 8 / 14 * 2; + start_found = 2; + } + break; + case DCA_SYNCWORD_CORE_14B_LE: + if (size == 4) { + pc1->framesize = CORE_FRAMESIZE(STATE_14(STATE_LE(state))) * 8 / 14 * 2; + start_found = 2; + } + break; + case DCA_SYNCWORD_SUBSTREAM: + if (size == 6) { + pc1->framesize = EXSS_FRAMESIZE(state); + start_found = 2; + } + break; + default: + av_assert0(0); + } + continue; + } + + if (pc1->lastmarker == DCA_SYNCWORD_CORE_BE) { + if (pc1->framesize > size + 2) + continue; + + if (start_found == 2 && IS_EXSS_MARKER(state)) { + pc1->framesize = size + 2; + start_found = 3; + continue; + } + + if (start_found == 3) { + if (size == pc1->framesize + 4) { + pc1->framesize += EXSS_FRAMESIZE(state); + start_found = 4; + } + continue; + } + } + + if (pc1->framesize > size) + continue; + if (IS_MARKER(state) && (pc1->lastmarker == CORE_MARKER(state) || pc1->lastmarker == DCA_SYNCWORD_SUBSTREAM)) { - if (pc1->framesize > pc1->size) - continue; pc->frame_start_found = 0; pc->state64 = -1; pc1->size = 0; @@ -96,8 +165,10 @@ static int dca_find_frame_end(DCAParseContext *pc1, const uint8_t *buf, } } } + pc->frame_start_found = start_found; pc->state64 = state; + pc1->size = size; return END_NOT_FOUND; } @@ -110,11 +181,11 @@ static av_cold int dca_parse_init(AVCodecParserContext *s) } static int dca_parse_params(const uint8_t *buf, int buf_size, int *duration, - int *sample_rate, int *framesize) + int *sample_rate) { GetBitContext gb; uint8_t hdr[12 + AV_INPUT_BUFFER_PADDING_SIZE] = { 0 }; - int ret, sample_blocks, sr_code; + int ret, sample_blocks; if (buf_size < 12) return AVERROR_INVALIDDATA; @@ -130,13 +201,8 @@ static int dca_parse_params(const uint8_t *buf, int buf_size, int *duration, return AVERROR_INVALIDDATA; *duration = 256 * (sample_blocks / 8); - *framesize = get_bits(&gb, 14) + 1; - if (*framesize < 95) - return AVERROR_INVALIDDATA; - - skip_bits(&gb, 6); - sr_code = get_bits(&gb, 4); - *sample_rate = avpriv_dca_sample_rates[sr_code]; + skip_bits(&gb, 20); + *sample_rate = avpriv_dca_sample_rates[get_bits(&gb, 4)]; if (*sample_rate == 0) return AVERROR_INVALIDDATA; @@ -164,7 +230,7 @@ static int dca_parse(AVCodecParserContext *s, AVCodecContext *avctx, } /* read the duration and sample rate from the frame header */ - if (!dca_parse_params(buf, buf_size, &duration, &sample_rate, &pc1->framesize)) { + if (!dca_parse_params(buf, buf_size, &duration, &sample_rate)) { if (!avctx->sample_rate) avctx->sample_rate = sample_rate; s->duration = av_rescale(duration, avctx->sample_rate, sample_rate);