| 31 | #include "rawdec.h" |
| 32 | |
| 33 | static int dts_probe(const AVProbeData *p) |
| 34 | { |
| 35 | const uint8_t *buf, *bufp; |
| 36 | uint32_t state = -1; |
| 37 | int markers[4*16] = {0}; |
| 38 | int exss_markers = 0, exss_nextpos = 0; |
| 39 | int sum, max, pos, ret, i; |
| 40 | int64_t diff = 0; |
| 41 | int diffcount = 1; |
| 42 | uint8_t hdr[DCA_CORE_FRAME_HEADER_SIZE + AV_INPUT_BUFFER_PADDING_SIZE] = { 0 }; |
| 43 | |
| 44 | for (pos = FFMIN(4096, p->buf_size); pos < p->buf_size - 2; pos += 2) { |
| 45 | int marker, wide_hdr, hdr_size, framesize; |
| 46 | DCACoreFrameHeader h; |
| 47 | GetBitContext gb; |
| 48 | |
| 49 | bufp = buf = p->buf + pos; |
| 50 | state = (state << 16) | bytestream_get_be16(&bufp); |
| 51 | |
| 52 | if (pos >= 4) { |
| 53 | if (AV_RL16(buf) || AV_RL16(buf-4)) { |
| 54 | diff += FFABS(((int16_t)AV_RL16(buf)) - (int16_t)AV_RL16(buf-4)); |
| 55 | diffcount ++; |
| 56 | } |
| 57 | } |
| 58 | |
| 59 | /* extension substream (EXSS) */ |
| 60 | if (state == DCA_SYNCWORD_SUBSTREAM) { |
| 61 | if (pos < exss_nextpos) |
| 62 | continue; |
| 63 | |
| 64 | init_get_bits(&gb, buf - 2, 96); |
| 65 | skip_bits_long(&gb, 42); |
| 66 | |
| 67 | wide_hdr = get_bits1(&gb); |
| 68 | hdr_size = get_bits(&gb, 8 + 4 * wide_hdr) + 1; |
| 69 | framesize = get_bits(&gb, 16 + 4 * wide_hdr) + 1; |
| 70 | if (hdr_size & 3 || framesize & 3) |
| 71 | continue; |
| 72 | if (hdr_size < 16 || framesize < hdr_size) |
| 73 | continue; |
| 74 | if (pos - 2 + hdr_size > p->buf_size) |
| 75 | continue; |
| 76 | if (av_crc(av_crc_get_table(AV_CRC_16_CCITT), 0xffff, buf + 3, hdr_size - 5)) |
| 77 | continue; |
| 78 | |
| 79 | if (pos == exss_nextpos) |
| 80 | exss_markers++; |
| 81 | else |
| 82 | exss_markers = FFMAX(1, exss_markers - 1); |
| 83 | exss_nextpos = pos + framesize; |
| 84 | continue; |
| 85 | } |
| 86 | |
| 87 | /* regular bitstream */ |
| 88 | if (state == DCA_SYNCWORD_CORE_BE && |
| 89 | (bytestream_get_be16(&bufp) & 0xFC00) == 0xFC00) |
| 90 | marker = 0; |
nothing calls this directly
no test coverage detected