| 244 | } |
| 245 | |
| 246 | static uint64_t dca_downmix_mask(int hb_mixdown, int normalized, const AVChannelLayout *input_layout) |
| 247 | { |
| 248 | /* |
| 249 | * AV_CODEC_ID_DTS |
| 250 | * |
| 251 | * For DTS-HD MA, doing a decoder downmix vs. an hb_audio_resample |
| 252 | * downmix can result in significant differences e.g. in terms of |
| 253 | * output bitrate using 24-bit FLAC. Letting the decoder decode |
| 254 | * the full bistream at least ensures decoding is lossless, at |
| 255 | * the expense of losing custom downmix coefficients that may |
| 256 | * exist in the bitstream. So, no decoder downmix for DTS. |
| 257 | * |
| 258 | * Long-term, a solution would be to have libavcodec's DTS decoder export |
| 259 | * downmix coefficients to a new type of AVFrame side data and pass that |
| 260 | * through to hb_audio_resample (similar to AV_FRAME_DATA_DOWNMIX_INFO). |
| 261 | */ |
| 262 | return 0; |
| 263 | } |
| 264 | |
| 265 | static uint64_t truehd_downmix_mask(int hb_mixdown, int normalized, const AVChannelLayout *input_layout) |
| 266 | { |