| 40 | } |
| 41 | |
| 42 | static int32_t ReadFrame (uint8_t* pBuf, const int32_t& iFileSize, const int32_t& bufPos) { |
| 43 | int32_t bytes_available = iFileSize - bufPos; |
| 44 | if (bytes_available < 4) { |
| 45 | return bytes_available; |
| 46 | } |
| 47 | uint8_t* ptr = pBuf + bufPos; |
| 48 | int32_t read_bytes = 0; |
| 49 | int32_t sps_count = 0; |
| 50 | int32_t pps_count = 0; |
| 51 | int32_t non_idr_pict_count = 0; |
| 52 | int32_t idr_pict_count = 0; |
| 53 | int32_t nal_deliminator = 0; |
| 54 | while (read_bytes < bytes_available - 4) { |
| 55 | bool has4ByteStartCode = ptr[0] == 0 && ptr[1] == 0 && ptr[2] == 0 && ptr[3] == 1; |
| 56 | bool has3ByteStartCode = false; |
| 57 | if (!has4ByteStartCode) { |
| 58 | has3ByteStartCode = ptr[0] == 0 && ptr[1] == 0 && ptr[2] == 1; |
| 59 | } |
| 60 | if (has4ByteStartCode || has3ByteStartCode) { |
| 61 | int32_t byteOffset = has4ByteStartCode ? 4 : 3; |
| 62 | uint8_t nal_unit_type = has4ByteStartCode ? (ptr[4] & 0x1F) : (ptr[3] & 0x1F); |
| 63 | if (nal_unit_type == 1) { |
| 64 | int32_t firstMBInSlice = readFirstMbInSlice (ptr + byteOffset); |
| 65 | if (++non_idr_pict_count >= 1 && idr_pict_count >= 1 && firstMBInSlice == 0) { |
| 66 | return read_bytes; |
| 67 | } |
| 68 | if (non_idr_pict_count >= 2 && firstMBInSlice == 0) { |
| 69 | return read_bytes; |
| 70 | } |
| 71 | } else if (nal_unit_type == 5) { |
| 72 | int32_t firstMBInSlice = readFirstMbInSlice (ptr + byteOffset); |
| 73 | if (++idr_pict_count >= 1 && non_idr_pict_count >= 1 && firstMBInSlice == 0) { |
| 74 | return read_bytes; |
| 75 | } |
| 76 | if (idr_pict_count >= 2 && firstMBInSlice == 0) { |
| 77 | return read_bytes; |
| 78 | } |
| 79 | } else if (nal_unit_type == 7) { |
| 80 | if ((++sps_count >= 1) && (non_idr_pict_count >= 1 || idr_pict_count >= 1)) { |
| 81 | return read_bytes; |
| 82 | } |
| 83 | if (sps_count == 2) return read_bytes; |
| 84 | } else if (nal_unit_type == 8) { |
| 85 | if (++pps_count >= 1 && (non_idr_pict_count >= 1 || idr_pict_count >= 1)) return read_bytes; |
| 86 | } else if (nal_unit_type == 9) { |
| 87 | if (++nal_deliminator == 2) { |
| 88 | return read_bytes; |
| 89 | } |
| 90 | } |
| 91 | if (read_bytes >= bytes_available - 4) { |
| 92 | return bytes_available; |
| 93 | } |
| 94 | read_bytes += 4; |
| 95 | ptr += 4; |
| 96 | } else { |
| 97 | ++ptr; |
| 98 | ++read_bytes; |
| 99 | } |
no test coverage detected