From 482d98f69b2eb7a7b0b5054101a43db384e9432b Mon Sep 17 00:00:00 2001 From: Anssi Hannula Date: Sat, 29 Jan 2011 03:36:30 +0200 Subject: spdifenc: IEC 61937 encapsulation of DTS-HD for HDMI Signed-off-by: Janne Grunau --- libavformat/spdifenc.c | 148 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 148 insertions(+) (limited to 'libavformat/spdifenc.c') diff --git a/libavformat/spdifenc.c b/libavformat/spdifenc.c index 3eea31e953..3c6fd73dbe 100644 --- a/libavformat/spdifenc.c +++ b/libavformat/spdifenc.c @@ -48,9 +48,12 @@ #include "spdif.h" #include "libavcodec/ac3.h" #include "libavcodec/dca.h" +#include "libavcodec/dcadata.h" #include "libavcodec/aacadtsdec.h" +#include "libavutil/opt.h" typedef struct IEC61937Context { + const AVClass *av_class; enum IEC61937DataType data_type;///< burst info - reference to type of payload of the data-burst int length_code; ///< length code in bits or bytes, depending on data type int pkt_offset; ///< data burst repetition period in bytes @@ -68,11 +71,24 @@ typedef struct IEC61937Context { int hd_buf_count; ///< number of frames in the hd audio buffer int hd_buf_filled; ///< amount of bytes in the hd audio buffer + int dtshd_skip; ///< counter used for skipping DTS-HD frames + + /* AVOptions: */ + int dtshd_rate; + int dtshd_fallback; + /// function, which generates codec dependent header information. /// Sets data_type and pkt_offset, and length_code, out_bytes, out_buf if necessary int (*header_info) (AVFormatContext *s, AVPacket *pkt); } IEC61937Context; +static const AVOption options[] = { +{ "dtshd_rate", "mux complete DTS frames in HD mode at the specified IEC958 rate (in Hz, default 0=disabled)", offsetof(IEC61937Context, dtshd_rate), FF_OPT_TYPE_INT, 0, 0, 768000, AV_OPT_FLAG_ENCODING_PARAM }, +{ "dtshd_fallback_time", "min secs to strip HD for after an overflow (-1: till the end, default 60)", offsetof(IEC61937Context, dtshd_fallback), FF_OPT_TYPE_INT, 60, -1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM }, +{ NULL }, +}; + +static const AVClass class = { "spdif", av_default_item_name, options, LIBAVUTIL_VERSION_INT }; static int spdif_header_ac3(AVFormatContext *s, AVPacket *pkt) { @@ -115,15 +131,125 @@ static int spdif_header_eac3(AVFormatContext *s, AVPacket *pkt) return 0; } +/* + * DTS type IV (DTS-HD) can be transmitted with various frame repetition + * periods; longer repetition periods allow for longer packets and therefore + * higher bitrate. Longer repetition periods mean that the constant bitrate of + * the outputted IEC 61937 stream is higher. + * The repetition period is measured in IEC 60958 frames (4 bytes). + */ +enum { + DTS4_REP_PER_512 = 0x0, + DTS4_REP_PER_1024 = 0x1, + DTS4_REP_PER_2048 = 0x2, + DTS4_REP_PER_4096 = 0x3, + DTS4_REP_PER_8192 = 0x4, + DTS4_REP_PER_16384 = 0x5, +}; + +static int spdif_dts4_subtype(int period) +{ + switch (period) { + case 512: return DTS4_REP_PER_512; + case 1024: return DTS4_REP_PER_1024; + case 2048: return DTS4_REP_PER_2048; + case 4096: return DTS4_REP_PER_4096; + case 8192: return DTS4_REP_PER_8192; + case 16384: return DTS4_REP_PER_16384; + } + return -1; +} + +static int spdif_header_dts4(AVFormatContext *s, AVPacket *pkt, int core_size, + int sample_rate, int blocks) +{ + IEC61937Context *ctx = s->priv_data; + static const char dtshd_start_code[10] = { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfe, 0xfe }; + int pkt_size = pkt->size; + int period; + int subtype; + + if (!core_size) { + av_log(s, AV_LOG_ERROR, "HD mode not supported for this format\n"); + return AVERROR(EINVAL); + } + + if (!sample_rate) { + av_log(s, AV_LOG_ERROR, "Unknown DTS sample rate for HD\n"); + return AVERROR_INVALIDDATA; + } + + period = ctx->dtshd_rate * (blocks << 5) / sample_rate; + subtype = spdif_dts4_subtype(period); + + if (subtype < 0) { + av_log(s, AV_LOG_ERROR, "Specified HD rate of %d Hz would require an " + "impossible repetition period of %d for the current DTS stream" + " (blocks = %d, sample rate = %d)\n", ctx->dtshd_rate, period, + blocks << 5, sample_rate); + return AVERROR(EINVAL); + } + + /* set pkt_offset and DTS IV subtype according to the requested output + * rate */ + ctx->pkt_offset = period * 4; + ctx->data_type = IEC61937_DTSHD | subtype << 8; + + /* If the bitrate is too high for transmitting at the selected + * repetition period setting, strip DTS-HD until a good amount + * of consecutive non-overflowing HD frames have been observed. + * This generally only happens if the caller is cramming a Master + * Audio stream into 192kHz IEC 60958 (which may or may not fit). */ + if (sizeof(dtshd_start_code) + 2 + pkt_size + > ctx->pkt_offset - BURST_HEADER_SIZE && core_size) { + if (!ctx->dtshd_skip) + av_log(s, AV_LOG_WARNING, "DTS-HD bitrate too high, " + "temporarily sending core only\n"); + if (ctx->dtshd_fallback > 0) + ctx->dtshd_skip = sample_rate * ctx->dtshd_fallback / (blocks << 5); + else + /* skip permanently (-1) or just once (0) */ + ctx->dtshd_skip = 1; + } + if (ctx->dtshd_skip && core_size) { + pkt_size = core_size; + if (ctx->dtshd_fallback >= 0) + --ctx->dtshd_skip; + } + + ctx->out_bytes = sizeof(dtshd_start_code) + 2 + pkt_size; + ctx->length_code = ctx->out_bytes; + + ctx->hd_buf = av_fast_realloc(ctx->hd_buf, &ctx->hd_buf_size, + ctx->out_bytes); + if (!ctx->hd_buf) + return AVERROR(ENOMEM); + + ctx->out_buf = ctx->hd_buf; + + memcpy(ctx->hd_buf, dtshd_start_code, sizeof(dtshd_start_code)); + AV_WB16(ctx->hd_buf + sizeof(dtshd_start_code), pkt_size); + memcpy(ctx->hd_buf + sizeof(dtshd_start_code) + 2, pkt->data, pkt_size); + + return 0; +} + static int spdif_header_dts(AVFormatContext *s, AVPacket *pkt) { IEC61937Context *ctx = s->priv_data; uint32_t syncword_dts = AV_RB32(pkt->data); int blocks; + int sample_rate = 0; + int core_size = 0; + + if (pkt->size < 9) + return AVERROR_INVALIDDATA; switch (syncword_dts) { case DCA_MARKER_RAW_BE: blocks = (AV_RB16(pkt->data + 4) >> 2) & 0x7f; + core_size = ((AV_RB24(pkt->data + 5) >> 4) & 0x3fff) + 1; + sample_rate = dca_sample_rates[(pkt->data[8] >> 2) & 0x0f]; break; case DCA_MARKER_RAW_LE: blocks = (AV_RL16(pkt->data + 4) >> 2) & 0x7f; @@ -138,11 +264,22 @@ static int spdif_header_dts(AVFormatContext *s, AVPacket *pkt) (((pkt->data[4] & 0x07) << 4) | ((pkt->data[7] & 0x3f) >> 2)); ctx->extra_bswap = 1; break; + case DCA_HD_MARKER: + /* We only handle HD frames that are paired with core. However, + sometimes DTS-HD streams with core have a stray HD frame without + core in the beginning of the stream. */ + av_log(s, AV_LOG_ERROR, "stray DTS-HD frame\n"); + return AVERROR_INVALIDDATA; default: av_log(s, AV_LOG_ERROR, "bad DTS syncword 0x%x\n", syncword_dts); return AVERROR_INVALIDDATA; } blocks++; + + if (ctx->dtshd_rate) + /* DTS type IV output requested */ + return spdif_header_dts4(s, pkt, core_size, sample_rate, blocks); + switch (blocks) { case 512 >> 5: ctx->data_type = IEC61937_DTS1; break; case 1024 >> 5: ctx->data_type = IEC61937_DTS2; break; @@ -152,6 +289,13 @@ static int spdif_header_dts(AVFormatContext *s, AVPacket *pkt) blocks << 5); return AVERROR(ENOSYS); } + + /* discard extraneous data by default */ + if (core_size && core_size < pkt->size) { + ctx->out_bytes = core_size; + ctx->length_code = core_size << 3; + } + ctx->pkt_offset = blocks << 7; if (ctx->out_bytes == ctx->pkt_offset) { @@ -159,6 +303,9 @@ static int spdif_header_dts(AVFormatContext *s, AVPacket *pkt) * preamble as it would not fit in there. This is the case for dts * discs and dts-in-wav. */ ctx->use_preamble = 0; + } else if (ctx->out_bytes > ctx->pkt_offset - BURST_HEADER_SIZE) { + av_log_ask_for_sample(s, "Unrecognized large DTS frame."); + /* This will fail with a "bitrate too high" in the caller */ } return 0; @@ -393,4 +540,5 @@ AVOutputFormat ff_spdif_muxer = { spdif_write_header, spdif_write_packet, spdif_write_trailer, + .priv_class = &class, }; -- cgit v1.2.3