diff options
| -rw-r--r-- | Changelog | 2 | ||||
| -rw-r--r-- | libavformat/spdifenc.c | 66 |
2 files changed, 67 insertions, 1 deletions
@@ -55,7 +55,7 @@ version <next>: - Win64 support for optimized asm functions - MJPEG/AVI1 to JPEG/JFIF bitstream filter - ASS subtitle encoder and decoder -- IEC 61937 encapsulation for E-AC3 (for HDMI passthrough) +- IEC 61937 encapsulation for E-AC3 and TrueHD (for HDMI passthrough) - overlay filter added - rename aspect filter to setdar, and pixelaspect to setsar - IEC 61937 demuxer diff --git a/libavformat/spdifenc.c b/libavformat/spdifenc.c index 0dcf98ce0b..d362f82a09 100644 --- a/libavformat/spdifenc.c +++ b/libavformat/spdifenc.c @@ -211,6 +211,66 @@ static int spdif_header_aac(AVFormatContext *s, AVPacket *pkt) return 0; } + +/* + * It seems Dolby TrueHD frames have to be encapsulated in MAT frames before + * they can be encapsulated in IEC 61937. + * Here we encapsulate 24 TrueHD frames in a single MAT frame, padding them + * to achieve constant rate. + * The actual format of a MAT frame is unknown, but the below seems to work. + * However, it seems it is not actually necessary for the 24 TrueHD frames to + * be in an exact alignment with the MAT frame. + */ +#define MAT_FRAME_SIZE 61424 +#define TRUEHD_FRAME_OFFSET 2560 +#define MAT_MIDDLE_CODE_OFFSET -4 + +static int spdif_header_truehd(AVFormatContext *s, AVPacket *pkt) +{ + IEC958Context *ctx = s->priv_data; + int mat_code_length = 0; + const char mat_end_code[16] = { 0xC3, 0xC2, 0xC0, 0xC4, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x97, 0x11 }; + + if (!ctx->hd_buf_count) { + const char mat_start_code[20] = { 0x07, 0x9E, 0x00, 0x03, 0x84, 0x01, 0x01, 0x01, 0x80, 0x00, 0x56, 0xA5, 0x3B, 0xF4, 0x81, 0x83, 0x49, 0x80, 0x77, 0xE0 }; + mat_code_length = sizeof(mat_start_code) + BURST_HEADER_SIZE; + memcpy(ctx->hd_buf, mat_start_code, sizeof(mat_start_code)); + + } else if (ctx->hd_buf_count == 12) { + const char mat_middle_code[12] = { 0xC3, 0xC1, 0x42, 0x49, 0x3B, 0xFA, 0x82, 0x83, 0x49, 0x80, 0x77, 0xE0 }; + mat_code_length = sizeof(mat_middle_code) + MAT_MIDDLE_CODE_OFFSET; + memcpy(&ctx->hd_buf[12 * TRUEHD_FRAME_OFFSET - BURST_HEADER_SIZE + MAT_MIDDLE_CODE_OFFSET], + mat_middle_code, sizeof(mat_middle_code)); + } + + if (pkt->size > TRUEHD_FRAME_OFFSET - mat_code_length) { + /* if such frames exist, we'd need some more complex logic to + * distribute the TrueHD frames in the MAT frame */ + av_log(s, AV_LOG_ERROR, "TrueHD frame too big, %d bytes\n", pkt->size); + av_log_ask_for_sample(s, NULL); + return -1; + } + + memcpy(&ctx->hd_buf[ctx->hd_buf_count * TRUEHD_FRAME_OFFSET - BURST_HEADER_SIZE + mat_code_length], + pkt->data, pkt->size); + memset(&ctx->hd_buf[ctx->hd_buf_count * TRUEHD_FRAME_OFFSET - BURST_HEADER_SIZE + mat_code_length + pkt->size], + 0, TRUEHD_FRAME_OFFSET - pkt->size - mat_code_length); + + if (++ctx->hd_buf_count < 24){ + ctx->pkt_offset = 0; + return 0; + } + memcpy(&ctx->hd_buf[MAT_FRAME_SIZE - sizeof(mat_end_code)], mat_end_code, sizeof(mat_end_code)); + ctx->hd_buf_count = 0; + + ctx->data_type = IEC958_TRUEHD; + ctx->pkt_offset = 61440; + ctx->out_buf = ctx->hd_buf; + ctx->out_bytes = MAT_FRAME_SIZE; + ctx->length_code = MAT_FRAME_SIZE; + return 0; +} + static int spdif_write_header(AVFormatContext *s) { IEC958Context *ctx = s->priv_data; @@ -233,6 +293,12 @@ static int spdif_write_header(AVFormatContext *s) case CODEC_ID_AAC: ctx->header_info = spdif_header_aac; break; + case CODEC_ID_TRUEHD: + ctx->header_info = spdif_header_truehd; + ctx->hd_buf = av_malloc(MAT_FRAME_SIZE); + if (!ctx->hd_buf) + return AVERROR(ENOMEM); + break; default: av_log(s, AV_LOG_ERROR, "codec not supported\n"); return -1; |