[FFmpeg-devel] [PATCH] avcodec/ac3: add support for dependent stream
Paul B Mahol
onemda at gmail.com
Tue Mar 27 14:57:34 EEST 2018
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
libavcodec/ac3_parser.c | 2 +-
libavcodec/ac3dec.c | 152 +++++++++++++++++++++++++++++++++++++++---------
libavcodec/ac3dec.h | 9 ++-
libavcodec/eac3dec.c | 11 +---
4 files changed, 134 insertions(+), 40 deletions(-)
diff --git a/libavcodec/ac3_parser.c b/libavcodec/ac3_parser.c
index 1015245a90..f4618bf215 100644
--- a/libavcodec/ac3_parser.c
+++ b/libavcodec/ac3_parser.c
@@ -218,8 +218,8 @@ static int ac3_sync(uint64_t state, AACAC3ParseContext *hdr_info,
else if (hdr_info->codec_id == AV_CODEC_ID_NONE)
hdr_info->codec_id = AV_CODEC_ID_AC3;
- *need_next_header = (hdr.frame_type != EAC3_FRAME_TYPE_AC3_CONVERT);
*new_frame_start = (hdr.frame_type != EAC3_FRAME_TYPE_DEPENDENT);
+ *need_next_header = *new_frame_start || (hdr.frame_type != EAC3_FRAME_TYPE_AC3_CONVERT);
return hdr.frame_size;
}
diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c
index 244a18323f..a6aff333e6 100644
--- a/libavcodec/ac3dec.c
+++ b/libavcodec/ac3dec.c
@@ -106,6 +106,25 @@ static const uint8_t ac3_default_coeffs[8][5][2] = {
{ { 2, 7 }, { 5, 5 }, { 7, 2 }, { 6, 7 }, { 7, 6 }, },
};
+static const uint64_t custom_channel_map_locations[16][2] = {
+ { 1, AV_CH_FRONT_LEFT },
+ { 1, AV_CH_FRONT_CENTER },
+ { 1, AV_CH_FRONT_RIGHT },
+ { 1, AV_CH_SIDE_LEFT },
+ { 1, AV_CH_SIDE_RIGHT },
+ { 0, AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER },
+ { 0, AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT },
+ { 0, AV_CH_BACK_CENTER },
+ { 0, AV_CH_TOP_CENTER },
+ { 0, AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT },
+ { 0, AV_CH_WIDE_LEFT | AV_CH_WIDE_RIGHT },
+ { 0, AV_CH_TOP_FRONT_LEFT | AV_CH_TOP_FRONT_RIGHT},
+ { 0, AV_CH_TOP_FRONT_CENTER },
+ { 0, AV_CH_TOP_BACK_LEFT | AV_CH_TOP_BACK_RIGHT },
+ { 0, AV_CH_LOW_FREQUENCY_2 },
+ { 1, AV_CH_LOW_FREQUENCY },
+};
+
/**
* Symmetrical Dequantization
* reference: Section 7.3.3 Expansion of Mantissas for Symmetrical Quantization
@@ -317,6 +336,7 @@ static int parse_frame_header(AC3DecodeContext *s)
s->fbw_channels = s->channels - s->lfe_on;
s->lfe_ch = s->fbw_channels + 1;
s->frame_size = hdr.frame_size;
+ s->superframe_size += hdr.frame_size;
s->preferred_downmix = AC3_DMIXMOD_NOTINDICATED;
s->center_mix_level = hdr.center_mix_level;
s->center_mix_level_ltrt = 4; // -3.0dB
@@ -683,7 +703,7 @@ static void do_rematrixing(AC3DecodeContext *s)
* Convert frequency domain coefficients to time-domain audio samples.
* reference: Section 7.9.4 Transformation Equations
*/
-static inline void do_imdct(AC3DecodeContext *s, int channels)
+static inline void do_imdct(AC3DecodeContext *s, int channels, int offset)
{
int ch;
@@ -695,25 +715,25 @@ static inline void do_imdct(AC3DecodeContext *s, int channels)
x[i] = s->transform_coeffs[ch][2 * i];
s->imdct_256.imdct_half(&s->imdct_256, s->tmp_output, x);
#if USE_FIXED
- s->fdsp->vector_fmul_window_scaled(s->outptr[ch - 1], s->delay[ch - 1],
+ s->fdsp->vector_fmul_window_scaled(s->outptr[ch - 1], s->delay[ch - 1 + offset],
s->tmp_output, s->window, 128, 8);
#else
- s->fdsp->vector_fmul_window(s->outptr[ch - 1], s->delay[ch - 1],
+ s->fdsp->vector_fmul_window(s->outptr[ch - 1], s->delay[ch - 1 + offset],
s->tmp_output, s->window, 128);
#endif
for (i = 0; i < 128; i++)
x[i] = s->transform_coeffs[ch][2 * i + 1];
- s->imdct_256.imdct_half(&s->imdct_256, s->delay[ch - 1], x);
+ s->imdct_256.imdct_half(&s->imdct_256, s->delay[ch - 1 + offset], x);
} else {
s->imdct_512.imdct_half(&s->imdct_512, s->tmp_output, s->transform_coeffs[ch]);
#if USE_FIXED
- s->fdsp->vector_fmul_window_scaled(s->outptr[ch - 1], s->delay[ch - 1],
+ s->fdsp->vector_fmul_window_scaled(s->outptr[ch - 1], s->delay[ch - 1 + offset],
s->tmp_output, s->window, 128, 8);
#else
- s->fdsp->vector_fmul_window(s->outptr[ch - 1], s->delay[ch - 1],
+ s->fdsp->vector_fmul_window(s->outptr[ch - 1], s->delay[ch - 1 + offset],
s->tmp_output, s->window, 128);
#endif
- memcpy(s->delay[ch - 1], s->tmp_output + 128, 128 * sizeof(FFTSample));
+ memcpy(s->delay[ch - 1 + offset], s->tmp_output + 128, 128 * sizeof(FFTSample));
}
}
}
@@ -1063,7 +1083,7 @@ static inline int coupling_coordinates(AC3DecodeContext *s, int blk)
/**
* Decode a single audio block from the AC-3 bitstream.
*/
-static int decode_audio_block(AC3DecodeContext *s, int blk)
+static int decode_audio_block(AC3DecodeContext *s, int blk, int offset)
{
int fbw_channels = s->fbw_channels;
int channel_mode = s->channel_mode;
@@ -1426,7 +1446,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
ac3_upmix_delay(s);
}
- do_imdct(s, s->channels);
+ do_imdct(s, s->channels, offset);
if (downmix_output) {
#if USE_FIXED
@@ -1449,7 +1469,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
s->out_channels, s->fbw_channels, 128);
}
- do_imdct(s, s->out_channels);
+ do_imdct(s, s->out_channels, offset);
}
return 0;
@@ -1463,14 +1483,16 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
{
AVFrame *frame = data;
const uint8_t *buf = avpkt->data;
- int buf_size = avpkt->size;
+ int buf_size, full_buf_size = avpkt->size;
AC3DecodeContext *s = avctx->priv_data;
- int blk, ch, err, ret;
+ int blk, ch, err, offset, ret;
const uint8_t *channel_map;
+ uint8_t extended_channel_map[AC3_MAX_CHANNELS * 2];
const SHORTFLOAT *output[AC3_MAX_CHANNELS];
enum AVMatrixEncoding matrix_encoding;
AVDownmixInfo *downmix_info;
+ buf_size = full_buf_size;
/* copy input buffer to decoder context to avoid reading past the end
of the buffer, which can be caused by a damaged input stream. */
if (buf_size >= 2 && AV_RB16(buf) == 0x770B) {
@@ -1488,6 +1510,7 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
av_lfg_init_from_data(&s->dith_state, s->input_buffer, FFMIN(buf_size, AC3_FRAME_BUFFER_SIZE));
buf = s->input_buffer;
+dependent_frame:
/* initialize the GetBitContext with the start of valid AC-3 Frame */
if ((ret = init_get_bits8(&s->gbc, buf, buf_size)) < 0)
return ret;
@@ -1511,7 +1534,7 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
break;
case AAC_AC3_PARSE_ERROR_FRAME_TYPE:
/* skip frame if CRC is ok. otherwise use error concealment. */
- /* TODO: add support for substreams and dependent frames */
+ /* TODO: add support for substreams */
if (s->frame_type == EAC3_FRAME_TYPE_DEPENDENT || s->substreamid) {
av_log(avctx, AV_LOG_DEBUG,
"unsupported frame type %d: skipping frame\n",
@@ -1532,7 +1555,7 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
} else {
/* check that reported frame size fits in input buffer */
if (s->frame_size > buf_size) {
- av_log(avctx, AV_LOG_ERROR, "incomplete frame\n");
+ av_log(avctx, AV_LOG_ERROR, "incomplete frame %d %d\n", s->frame_size, buf_size);
err = AAC_AC3_PARSE_ERROR_FRAME_SIZE;
} else if (avctx->err_recognition & (AV_EF_CRCCHECK|AV_EF_CAREFUL)) {
/* check for crc mismatch */
@@ -1594,29 +1617,25 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
if (s->bitstream_mode == 0x7 && s->channels > 1)
avctx->audio_service_type = AV_AUDIO_SERVICE_TYPE_KARAOKE;
- /* get output buffer */
- frame->nb_samples = s->num_blocks * AC3_BLOCK_SIZE;
- if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
- return ret;
-
/* decode the audio blocks */
channel_map = ff_ac3_dec_channel_map[s->output_mode & ~AC3_OUTPUT_LFEON][s->lfe_on];
+ offset = s->frame_type == EAC3_FRAME_TYPE_DEPENDENT ? AC3_MAX_CHANNELS : 0;
for (ch = 0; ch < AC3_MAX_CHANNELS; ch++) {
- output[ch] = s->output[ch];
- s->outptr[ch] = s->output[ch];
+ output[ch] = s->output[ch + offset];
+ s->outptr[ch] = s->output[ch + offset];
}
for (ch = 0; ch < s->channels; ch++) {
if (ch < s->out_channels)
- s->outptr[channel_map[ch]] = (SHORTFLOAT *)frame->data[ch];
+ s->outptr[channel_map[ch]] = s->output_buffer[ch + offset];
}
for (blk = 0; blk < s->num_blocks; blk++) {
- if (!err && decode_audio_block(s, blk)) {
+ if (!err && decode_audio_block(s, blk, offset)) {
av_log(avctx, AV_LOG_ERROR, "error decoding the audio block\n");
err = 1;
}
if (err)
for (ch = 0; ch < s->out_channels; ch++)
- memcpy(((SHORTFLOAT*)frame->data[ch]) + AC3_BLOCK_SIZE*blk, output[ch], AC3_BLOCK_SIZE*sizeof(SHORTFLOAT));
+ memcpy(s->output_buffer[ch + offset] + AC3_BLOCK_SIZE*blk, output[ch], AC3_BLOCK_SIZE*sizeof(SHORTFLOAT));
for (ch = 0; ch < s->out_channels; ch++)
output[ch] = s->outptr[channel_map[ch]];
for (ch = 0; ch < s->out_channels; ch++) {
@@ -1625,11 +1644,88 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
}
}
- frame->decode_error_flags = err ? FF_DECODE_ERROR_INVALID_BITSTREAM : 0;
-
/* keep last block for error concealment in next frame */
for (ch = 0; ch < s->out_channels; ch++)
- memcpy(s->output[ch], output[ch], AC3_BLOCK_SIZE*sizeof(SHORTFLOAT));
+ memcpy(s->output[ch + offset], output[ch], AC3_BLOCK_SIZE*sizeof(SHORTFLOAT));
+
+ /* check if there is dependent frame */
+ if (buf_size > s->frame_size) {
+ AC3HeaderInfo hdr;
+ int err;
+
+ if ((ret = init_get_bits8(&s->gbc, buf + s->frame_size, buf_size - s->frame_size)) < 0)
+ return ret;
+
+ err = ff_ac3_parse_header(&s->gbc, &hdr);
+ if (err)
+ return err;
+
+ if (hdr.frame_type == EAC3_FRAME_TYPE_DEPENDENT) {
+ buf += s->frame_size;
+ buf_size -= s->frame_size;
+ s->prev_output_mode = s->output_mode;
+ goto dependent_frame;
+ }
+ }
+
+ frame->decode_error_flags = err ? FF_DECODE_ERROR_INVALID_BITSTREAM : 0;
+
+ for (ch = 0; ch < 16; ch++)
+ extended_channel_map[ch] = ch;
+
+ if (s->frame_type == EAC3_FRAME_TYPE_DEPENDENT) {
+ uint64_t ich_layout = avpriv_ac3_channel_layout_tab[s->prev_output_mode & ~AC3_OUTPUT_LFEON];
+ uint64_t channel_layout;
+ int extend = 0;
+
+ if (s->prev_output_mode & AC3_OUTPUT_LFEON)
+ ich_layout |= AV_CH_LOW_FREQUENCY;
+
+ channel_layout = ich_layout;
+ for (ch = 0; ch < 16; ch++) {
+ if (s->channel_map & (1 << (15 - ch))) {
+ channel_layout |= custom_channel_map_locations[ch][1];
+ }
+ }
+
+ avctx->channel_layout = channel_layout;
+ avctx->channels = av_get_channel_layout_nb_channels(channel_layout);
+
+ for (ch = 0; ch < 16; ch++) {
+ if (s->channel_map & (1 << (15 - ch))) {
+ if (custom_channel_map_locations[ch][0]) {
+ int index = av_get_channel_layout_channel_index(channel_layout,
+ custom_channel_map_locations[ch][1]);
+ if (index < 0)
+ return AVERROR_INVALIDDATA;
+ extended_channel_map[index] = offset + channel_map[extend++];
+ } else {
+ int i;
+
+ for (i = 0; i < 64; i++) {
+ if ((1LL << i) & custom_channel_map_locations[ch][1]) {
+ int index = av_get_channel_layout_channel_index(channel_layout,
+ 1LL << i);
+ if (index < 0)
+ return AVERROR_INVALIDDATA;
+ extended_channel_map[index] = offset + channel_map[extend++];
+ }
+ }
+ }
+ }
+ }
+ }
+
+ /* get output buffer */
+ frame->nb_samples = s->num_blocks * AC3_BLOCK_SIZE;
+ if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+ return ret;
+
+ for (ch = 0; ch < avctx->channels; ch++) {
+ int map = extended_channel_map[ch];
+ memcpy((SHORTFLOAT *)frame->data[ch], s->output_buffer[map],
+ s->num_blocks * AC3_BLOCK_SIZE * sizeof(SHORTFLOAT));
+ }
/*
* AVMatrixEncoding
@@ -1689,7 +1785,7 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data,
*got_frame_ptr = 1;
- return FFMIN(buf_size, s->frame_size);
+ return FFMIN(full_buf_size, s->superframe_size);
}
/**
diff --git a/libavcodec/ac3dec.h b/libavcodec/ac3dec.h
index aa4cf04f8a..551f4bbc1b 100644
--- a/libavcodec/ac3dec.h
+++ b/libavcodec/ac3dec.h
@@ -76,6 +76,7 @@ typedef struct AC3DecodeContext {
///@{
int frame_type; ///< frame type (strmtyp)
int substreamid; ///< substream identification
+ int superframe_size; ///< current superframe size, in bytes
int frame_size; ///< current frame size, in bytes
int bit_rate; ///< stream bit rate, in bits-per-second
int sample_rate; ///< sample frequency, in Hz
@@ -87,7 +88,7 @@ typedef struct AC3DecodeContext {
int dialog_normalization[2]; ///< dialog level in dBFS (dialnorm)
int compression_exists[2]; ///< compression field is valid for frame (compre)
int compression_gain[2]; ///< gain to apply for heavy compression (compr)
- int channel_map; ///< custom channel map
+ int channel_map; ///< custom channel map (chanmap)
int preferred_downmix; ///< Preferred 2-channel downmix mode (dmixmod)
int center_mix_level; ///< Center mix level index
int center_mix_level_ltrt; ///< Center mix level index for Lt/Rt (ltrtcmixlev)
@@ -164,6 +165,7 @@ typedef struct AC3DecodeContext {
SHORTFLOAT *downmix_coeffs[2]; ///< stereo downmix coefficients
int downmixed; ///< indicates if coeffs are currently downmixed
int output_mode; ///< output channel configuration
+ int prev_output_mode; ///< output channel configuration for previous frame
int out_channels; ///< number of output channels
///@}
@@ -239,11 +241,12 @@ typedef struct AC3DecodeContext {
///@name Aligned arrays
DECLARE_ALIGNED(16, int, fixed_coeffs)[AC3_MAX_CHANNELS][AC3_MAX_COEFS]; ///< fixed-point transform coefficients
DECLARE_ALIGNED(32, INTFLOAT, transform_coeffs)[AC3_MAX_CHANNELS][AC3_MAX_COEFS]; ///< transform coefficients
- DECLARE_ALIGNED(32, INTFLOAT, delay)[AC3_MAX_CHANNELS][AC3_BLOCK_SIZE]; ///< delay - added to the next block
+ DECLARE_ALIGNED(32, INTFLOAT, delay)[2 * AC3_MAX_CHANNELS][AC3_BLOCK_SIZE]; ///< delay - added to the next block
DECLARE_ALIGNED(32, INTFLOAT, window)[AC3_BLOCK_SIZE]; ///< window coefficients
DECLARE_ALIGNED(32, INTFLOAT, tmp_output)[AC3_BLOCK_SIZE]; ///< temporary storage for output before windowing
- DECLARE_ALIGNED(32, SHORTFLOAT, output)[AC3_MAX_CHANNELS][AC3_BLOCK_SIZE]; ///< output after imdct transform and windowing
+ DECLARE_ALIGNED(32, SHORTFLOAT, output)[2 * AC3_MAX_CHANNELS][AC3_BLOCK_SIZE]; ///< output after imdct transform and windowing
DECLARE_ALIGNED(32, uint8_t, input_buffer)[AC3_FRAME_BUFFER_SIZE + AV_INPUT_BUFFER_PADDING_SIZE]; ///< temp buffer to prevent overread
+ DECLARE_ALIGNED(32, SHORTFLOAT, output_buffer)[2 * AC3_MAX_CHANNELS][AC3_BLOCK_SIZE * 6]; ///< final output buffer
///@}
} AC3DecodeContext;
diff --git a/libavcodec/eac3dec.c b/libavcodec/eac3dec.c
index 6f6309f179..fe97d29032 100644
--- a/libavcodec/eac3dec.c
+++ b/libavcodec/eac3dec.c
@@ -303,13 +303,7 @@ static int ff_eac3_parse_header(AC3DecodeContext *s)
/* An E-AC-3 stream can have multiple independent streams which the
application can select from. each independent stream can also contain
dependent streams which are used to add or replace channels. */
- if (s->frame_type == EAC3_FRAME_TYPE_DEPENDENT) {
- if (!s->eac3_frame_dependent_found) {
- s->eac3_frame_dependent_found = 1;
- avpriv_request_sample(s->avctx, "Dependent substream decoding");
- }
- return AAC_AC3_PARSE_ERROR_FRAME_TYPE;
- } else if (s->frame_type == EAC3_FRAME_TYPE_RESERVED) {
+ if (s->frame_type == EAC3_FRAME_TYPE_RESERVED) {
av_log(s->avctx, AV_LOG_ERROR, "Reserved frame type\n");
return AAC_AC3_PARSE_ERROR_FRAME_TYPE;
}
@@ -355,7 +349,8 @@ static int ff_eac3_parse_header(AC3DecodeContext *s)
/* dependent stream channel map */
if (s->frame_type == EAC3_FRAME_TYPE_DEPENDENT) {
if (get_bits1(gbc)) {
- skip_bits(gbc, 16); // skip custom channel map
+ s->channel_map = get_bits(gbc, 16);
+ av_log(s->avctx, AV_LOG_DEBUG, "channel_map: %0X\n", s->channel_map);
}
}
--
2.11.0
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