* MLP parser
* Copyright (c) 2007 Ian Caulfield
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
- * @file mlp_parser.c
+ * @file
* MLP parser
*/
+#include <stdint.h>
+
+#include "libavutil/channel_layout.h"
#include "libavutil/crc.h"
-#include "bitstream.h"
+#include "libavutil/internal.h"
+#include "get_bits.h"
#include "parser.h"
#include "mlp_parser.h"
+#include "mlp.h"
static const uint8_t mlp_quants[16] = {
16, 20, 24, 0, 0, 0, 0, 0,
5, 6, 5, 5, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
+static const uint64_t mlp_layout[32] = {
+ AV_CH_LAYOUT_MONO,
+ AV_CH_LAYOUT_STEREO,
+ AV_CH_LAYOUT_2_1,
+ AV_CH_LAYOUT_2_2,
+ AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY,
+ AV_CH_LAYOUT_2_1|AV_CH_LOW_FREQUENCY,
+ AV_CH_LAYOUT_2_2|AV_CH_LOW_FREQUENCY,
+ AV_CH_LAYOUT_SURROUND,
+ AV_CH_LAYOUT_4POINT0,
+ AV_CH_LAYOUT_5POINT0,
+ AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY,
+ AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY,
+ AV_CH_LAYOUT_5POINT1,
+ AV_CH_LAYOUT_4POINT0,
+ AV_CH_LAYOUT_5POINT0,
+ AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY,
+ AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY,
+ AV_CH_LAYOUT_5POINT1,
+ AV_CH_LAYOUT_2_2|AV_CH_LOW_FREQUENCY,
+ AV_CH_LAYOUT_5POINT0,
+ AV_CH_LAYOUT_5POINT1,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
static const uint8_t thd_chancount[13] = {
// LR C LFE LRs LRvh LRc LRrs Cs Ts LRsd LRw Cvh LFE2
2, 1, 1, 2, 2, 2, 2, 1, 1, 2, 2, 1, 1
};
+static const uint64_t thd_layout[13] = {
+ AV_CH_FRONT_LEFT|AV_CH_FRONT_RIGHT, // LR
+ AV_CH_FRONT_CENTER, // C
+ AV_CH_LOW_FREQUENCY, // LFE
+ AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT, // LRs
+ AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT, // LRvh
+ AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER, // LRc
+ AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT, // LRrs
+ AV_CH_BACK_CENTER, // Cs
+ AV_CH_TOP_CENTER, // Ts
+ AV_CH_SURROUND_DIRECT_LEFT|AV_CH_SURROUND_DIRECT_RIGHT, // LRsd
+ AV_CH_WIDE_LEFT|AV_CH_WIDE_RIGHT, // LRw
+ AV_CH_TOP_FRONT_CENTER, // Cvh
+ AV_CH_LOW_FREQUENCY_2, // LFE2
+};
+
static int mlp_samplerate(int in)
{
if (in == 0xF)
return channels;
}
-static int crc_init = 0;
-static AVCRC crc_2D[1024];
-
-/** MLP uses checksums that seem to be based on the standard CRC algorithm,
- * but not (in implementation terms, the table lookup and XOR are reversed).
- * We can implement this behavior using a standard av_crc on all but the
- * last element, then XOR that with the last element.
- */
-
-static uint16_t mlp_checksum16(const uint8_t *buf, unsigned int buf_size)
+static uint64_t truehd_layout(int chanmap)
{
- uint16_t crc;
+ int i;
+ uint64_t layout = 0;
- if (!crc_init) {
- av_crc_init(crc_2D, 0, 16, 0x002D, sizeof(crc_2D));
- crc_init = 1;
- }
+ for (i = 0; i < 13; i++)
+ layout |= thd_layout[i] * ((chanmap >> i) & 1);
- crc = av_crc(crc_2D, 0, buf, buf_size - 2);
- crc ^= AV_RL16(buf + buf_size - 2);
- return crc;
+ return layout;
}
/** Read a major sync info header - contains high level information about
* the stream - sample rate, channel arrangement etc. Most of this
* information is not actually necessary for decoding, only for playback.
+ * gb must be a freshly initialized GetBitContext with no bits read.
*/
-int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, const uint8_t *buf,
- unsigned int buf_size)
+int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb)
{
- GetBitContext gb;
- int ratebits;
+ int ratebits, channel_arrangement;
uint16_t checksum;
- if (buf_size < 28) {
- av_log(log, AV_LOG_ERROR, "Packet too short, unable to read major sync\n");
+ assert(get_bits_count(gb) == 0);
+
+ if (gb->size_in_bits < 28 << 3) {
+ av_log(log, AV_LOG_ERROR, "packet too short, unable to read major sync\n");
return -1;
}
- checksum = mlp_checksum16(buf, 26);
- if (checksum != AV_RL16(buf+26)) {
- av_log(log, AV_LOG_ERROR, "Major sync info header checksum error\n");
- return -1;
+ checksum = ff_mlp_checksum16(gb->buffer, 26);
+ if (checksum != AV_RL16(gb->buffer+26)) {
+ av_log(log, AV_LOG_ERROR, "major sync info header checksum error\n");
+ return AVERROR_INVALIDDATA;
}
- init_get_bits(&gb, buf, buf_size * 8);
+ if (get_bits_long(gb, 24) != 0xf8726f) /* Sync words */
+ return AVERROR_INVALIDDATA;
- if (get_bits_long(&gb, 24) != 0xf8726f) /* Sync words */
- return -1;
-
- mh->stream_type = get_bits(&gb, 8);
+ mh->stream_type = get_bits(gb, 8);
if (mh->stream_type == 0xbb) {
- mh->group1_bits = mlp_quants[get_bits(&gb, 4)];
- mh->group2_bits = mlp_quants[get_bits(&gb, 4)];
+ mh->group1_bits = mlp_quants[get_bits(gb, 4)];
+ mh->group2_bits = mlp_quants[get_bits(gb, 4)];
- ratebits = get_bits(&gb, 4);
+ ratebits = get_bits(gb, 4);
mh->group1_samplerate = mlp_samplerate(ratebits);
- mh->group2_samplerate = mlp_samplerate(get_bits(&gb, 4));
+ mh->group2_samplerate = mlp_samplerate(get_bits(gb, 4));
- skip_bits(&gb, 11);
+ skip_bits(gb, 11);
- mh->channels_mlp = get_bits(&gb, 5);
+ channel_arrangement = get_bits(gb, 5);
+ mh->channels_mlp = mlp_channels[channel_arrangement];
+ mh->channel_layout_mlp = mlp_layout[channel_arrangement];
} else if (mh->stream_type == 0xba) {
mh->group1_bits = 24; // TODO: Is this information actually conveyed anywhere?
mh->group2_bits = 0;
- ratebits = get_bits(&gb, 4);
+ ratebits = get_bits(gb, 4);
mh->group1_samplerate = mlp_samplerate(ratebits);
mh->group2_samplerate = 0;
- skip_bits(&gb, 8);
+ skip_bits(gb, 4);
+
+ mh->channel_modifier_thd_stream0 = get_bits(gb, 2);
+ mh->channel_modifier_thd_stream1 = get_bits(gb, 2);
- mh->channels_thd_stream1 = get_bits(&gb, 5);
+ channel_arrangement = get_bits(gb, 5);
+ mh->channels_thd_stream1 = truehd_channels(channel_arrangement);
+ mh->channel_layout_thd_stream1 = truehd_layout(channel_arrangement);
- skip_bits(&gb, 2);
+ mh->channel_modifier_thd_stream2 = get_bits(gb, 2);
- mh->channels_thd_stream2 = get_bits(&gb, 13);
+ channel_arrangement = get_bits(gb, 13);
+ mh->channels_thd_stream2 = truehd_channels(channel_arrangement);
+ mh->channel_layout_thd_stream2 = truehd_layout(channel_arrangement);
} else
- return -1;
+ return AVERROR_INVALIDDATA;
mh->access_unit_size = 40 << (ratebits & 7);
mh->access_unit_size_pow2 = 64 << (ratebits & 7);
- skip_bits_long(&gb, 48);
+ skip_bits_long(gb, 48);
- mh->is_vbr = get_bits1(&gb);
+ mh->is_vbr = get_bits1(gb);
- mh->peak_bitrate = (get_bits(&gb, 15) * mh->group1_samplerate + 8) >> 4;
+ mh->peak_bitrate = (get_bits(gb, 15) * mh->group1_samplerate + 8) >> 4;
- mh->num_substreams = get_bits(&gb, 4);
+ mh->num_substreams = get_bits(gb, 4);
- skip_bits_long(&gb, 4 + 11 * 8);
+ skip_bits_long(gb, 4 + 11 * 8);
return 0;
}
int num_substreams;
} MLPParseContext;
+static av_cold int mlp_init(AVCodecParserContext *s)
+{
+ ff_mlp_init_crc();
+ return 0;
+}
+
static int mlp_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
for (i = 0; i < buf_size; i++) {
mp->pc.state = (mp->pc.state << 8) | buf[i];
- if ((mp->pc.state & 0xfffffffe) == 0xf8726fba) {
+ if ((mp->pc.state & 0xfffffffe) == 0xf8726fba &&
+ // ignore if we do not have the data for the start of header
+ mp->pc.index + i >= 7) {
mp->in_sync = 1;
mp->bytes_left = 0;
break;
sync_present = (AV_RB32(buf + 4) & 0xfffffffe) == 0xf8726fba;
if (!sync_present) {
- // First nibble of a frame is a parity check of the first few nibbles.
+ /* The first nibble of a frame is a parity check of the 4-byte
+ * access unit header and all the 2- or 4-byte substream headers. */
// Only check when this isn't a sync frame - syncs have a checksum.
parity_bits = 0;
goto lost_sync;
}
} else {
+ GetBitContext gb;
MLPHeaderInfo mh;
- if (ff_mlp_read_major_sync(avctx, &mh, buf + 4, buf_size - 4) < 0)
+ init_get_bits(&gb, buf + 4, (buf_size - 4) << 3);
+ if (ff_mlp_read_major_sync(avctx, &mh, &gb) < 0)
goto lost_sync;
-#ifdef CONFIG_AUDIO_NONSHORT
- avctx->bits_per_sample = mh.group1_bits;
- if (avctx->bits_per_sample > 16)
- avctx->sample_fmt = SAMPLE_FMT_S32;
-#endif
+ avctx->bits_per_raw_sample = mh.group1_bits;
+ if (avctx->bits_per_raw_sample > 16)
+ avctx->sample_fmt = AV_SAMPLE_FMT_S32;
+ else
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
avctx->sample_rate = mh.group1_samplerate;
- avctx->frame_size = mh.access_unit_size;
+ s->duration = mh.access_unit_size;
if (mh.stream_type == 0xbb) {
/* MLP stream */
- avctx->channels = mlp_channels[mh.channels_mlp];
+#if FF_API_REQUEST_CHANNELS
+FF_DISABLE_DEPRECATION_WARNINGS
+ if (avctx->request_channels > 0 && avctx->request_channels <= 2 &&
+ mh.num_substreams > 1) {
+ avctx->channels = 2;
+ avctx->channel_layout = AV_CH_LAYOUT_STEREO;
+ } else
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+ if (avctx->request_channel_layout == AV_CH_LAYOUT_STEREO &&
+ mh.num_substreams > 1) {
+ avctx->channels = 2;
+ avctx->channel_layout = AV_CH_LAYOUT_STEREO;
+ } else {
+ avctx->channels = mh.channels_mlp;
+ avctx->channel_layout = mh.channel_layout_mlp;
+ }
} else { /* mh.stream_type == 0xba */
/* TrueHD stream */
- if (mh.channels_thd_stream2)
- avctx->channels = truehd_channels(mh.channels_thd_stream2);
- else
- avctx->channels = truehd_channels(mh.channels_thd_stream1);
+#if FF_API_REQUEST_CHANNELS
+FF_DISABLE_DEPRECATION_WARNINGS
+ if (avctx->request_channels > 0 && avctx->request_channels <= 2 &&
+ mh.num_substreams > 1) {
+ avctx->channels = 2;
+ avctx->channel_layout = AV_CH_LAYOUT_STEREO;
+ } else if (avctx->request_channels > 0 &&
+ avctx->request_channels <= mh.channels_thd_stream1) {
+ avctx->channels = mh.channels_thd_stream1;
+ avctx->channel_layout = mh.channel_layout_thd_stream1;
+ } else
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+ if (avctx->request_channel_layout == AV_CH_LAYOUT_STEREO &&
+ mh.num_substreams > 1) {
+ avctx->channels = 2;
+ avctx->channel_layout = AV_CH_LAYOUT_STEREO;
+ } else if (avctx->request_channel_layout == mh.channel_layout_thd_stream1 ||
+ !mh.channels_thd_stream2) {
+ avctx->channels = mh.channels_thd_stream1;
+ avctx->channel_layout = mh.channel_layout_thd_stream1;
+ } else {
+ avctx->channels = mh.channels_thd_stream2;
+ avctx->channel_layout = mh.channel_layout_thd_stream2;
+ }
}
if (!mh.is_vbr) /* Stream is CBR */
return 1;
}
-AVCodecParser mlp_parser = {
- { CODEC_ID_MLP },
- sizeof(MLPParseContext),
- NULL,
- mlp_parse,
- NULL,
+AVCodecParser ff_mlp_parser = {
+ .codec_ids = { AV_CODEC_ID_MLP, AV_CODEC_ID_TRUEHD },
+ .priv_data_size = sizeof(MLPParseContext),
+ .parser_init = mlp_init,
+ .parser_parse = mlp_parse,
+ .parser_close = ff_parse_close,
};