static int dca_parse_params(const uint8_t *buf, int buf_size, int *duration,
int *sample_rate, int *framesize)
{
GetBitContext gb;
uint8_t hdr[12 + AV_INPUT_BUFFER_PADDING_SIZE] = { 0 };
int ret, sample_blocks, sr_code;
if (buf_size < 12)
return AVERROR_INVALIDDATA;
if ((ret = avpriv_dca_convert_bitstream(buf, 12, hdr, 12)) < 0)
return ret;
init_get_bits(&gb, hdr, 96);
skip_bits_long(&gb, 39);
sample_blocks = get_bits(&gb, 7) + 1;
if (sample_blocks < 8)
return AVERROR_INVALIDDATA;
*duration = 256 * (sample_blocks / 8);
*framesize = get_bits(&gb, 14) + 1;
if (*framesize < 95)
return AVERROR_INVALIDDATA;
skip_bits(&gb, 6);
sr_code = get_bits(&gb, 4);
*sample_rate = avpriv_dca_sample_rates[sr_code];
if (*sample_rate == 0)
return AVERROR_INVALIDDATA;
return 0;
}
static int convert_bitstream(const uint8_t *src, int src_size, uint8_t *dst, int max_size)
{
switch (AV_RB32(src)) {
case DCA_SYNCWORD_CORE_BE:
case DCA_SYNCWORD_SUBSTREAM:
memcpy(dst, src, src_size);
return src_size;
case DCA_SYNCWORD_CORE_LE:
case DCA_SYNCWORD_CORE_14B_BE:
case DCA_SYNCWORD_CORE_14B_LE:
return avpriv_dca_convert_bitstream(src, src_size, dst, max_size);
default:
return AVERROR_INVALIDDATA;
}
}
static int dts_probe(AVProbeData *p)
{
const uint8_t *buf, *bufp;
uint32_t state = -1;
int markers[4*16] = {0};
int sum, max, i;
int64_t diff = 0;
uint8_t hdr[12 + FF_INPUT_BUFFER_PADDING_SIZE] = { 0 };
buf = p->buf + FFMIN(4096, p->buf_size);
for(; buf < (p->buf+p->buf_size)-2; buf+=2) {
int marker, sample_blocks, sample_rate, sr_code, framesize;
int lfe;
GetBitContext gb;
bufp = buf;
state = (state << 16) | bytestream_get_be16(&bufp);
if (buf - p->buf >= 4)
diff += FFABS(((int16_t)AV_RL16(buf)) - (int16_t)AV_RL16(buf-4));
/* regular bitstream */
if (state == DCA_SYNCWORD_CORE_BE)
marker = 0;
else if (state == DCA_SYNCWORD_CORE_LE)
marker = 1;
/* 14 bits big-endian bitstream */
else if (state == DCA_SYNCWORD_CORE_14B_BE &&
(bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
marker = 2;
/* 14 bits little-endian bitstream */
else if (state == DCA_SYNCWORD_CORE_14B_LE &&
(bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007)
marker = 3;
else
continue;
if (avpriv_dca_convert_bitstream(buf-2, 12, hdr, 12) < 0)
continue;
init_get_bits(&gb, hdr, 96);
skip_bits_long(&gb, 39);
sample_blocks = get_bits(&gb, 7) + 1;
if (sample_blocks < 8)
continue;
framesize = get_bits(&gb, 14) + 1;
if (framesize < 95)
continue;
skip_bits(&gb, 6);
sr_code = get_bits(&gb, 4);
sample_rate = avpriv_dca_sample_rates[sr_code];
if (sample_rate == 0)
continue;
get_bits(&gb, 5);
if (get_bits(&gb, 1))
continue;
skip_bits_long(&gb, 9);
lfe = get_bits(&gb, 2);
if (lfe > 2)
continue;
marker += 4* sr_code;
markers[marker] ++;
}
sum = max = 0;
for (i=0; i<FF_ARRAY_ELEMS(markers); i++) {
sum += markers[i];
if (markers[max] < markers[i])
max = i;
}
if (markers[max] > 3 && p->buf_size / markers[max] < 32*1024 &&
markers[max] * 4 > sum * 3 &&
diff / p->buf_size > 200)
return AVPROBE_SCORE_EXTENSION + 1;
return 0;
}
static int dcadec_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
DCAContext *s = avctx->priv_data;
AVFrame *frame = data;
uint8_t *input = avpkt->data;
int input_size = avpkt->size;
int i, ret, prev_packet = s->packet;
uint32_t mrk;
if (input_size < MIN_PACKET_SIZE || input_size > MAX_PACKET_SIZE) {
av_log(avctx, AV_LOG_ERROR, "Invalid packet size\n");
return AVERROR_INVALIDDATA;
}
// Convert input to BE format
mrk = AV_RB32(input);
if (mrk != DCA_SYNCWORD_CORE_BE && mrk != DCA_SYNCWORD_SUBSTREAM) {
av_fast_padded_malloc(&s->buffer, &s->buffer_size, input_size);
if (!s->buffer)
return AVERROR(ENOMEM);
for (i = 0, ret = AVERROR_INVALIDDATA; i < input_size - MIN_PACKET_SIZE + 1 && ret < 0; i++)
ret = avpriv_dca_convert_bitstream(input + i, input_size - i, s->buffer, s->buffer_size);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Not a valid DCA frame\n");
return ret;
}
input = s->buffer;
input_size = ret;
}
s->packet = 0;
// Parse backward compatible core sub-stream
if (AV_RB32(input) == DCA_SYNCWORD_CORE_BE) {
int frame_size;
if ((ret = ff_dca_core_parse(&s->core, input, input_size)) < 0)
return ret;
s->packet |= DCA_PACKET_CORE;
// EXXS data must be aligned on 4-byte boundary
frame_size = FFALIGN(s->core.frame_size, 4);
if (input_size - 4 > frame_size) {
input += frame_size;
input_size -= frame_size;
}
}
if (!s->core_only) {
DCAExssAsset *asset = NULL;
// Parse extension sub-stream (EXSS)
if (AV_RB32(input) == DCA_SYNCWORD_SUBSTREAM) {
if ((ret = ff_dca_exss_parse(&s->exss, input, input_size)) < 0) {
if (avctx->err_recognition & AV_EF_EXPLODE)
return ret;
} else {
s->packet |= DCA_PACKET_EXSS;
asset = &s->exss.assets[0];
}
}
// Parse XLL component in EXSS
if (asset && (asset->extension_mask & DCA_EXSS_XLL)) {
if ((ret = ff_dca_xll_parse(&s->xll, input, asset)) < 0) {
// Conceal XLL synchronization error
if (ret == AVERROR(EAGAIN)
&& (prev_packet & DCA_PACKET_XLL)
&& (s->packet & DCA_PACKET_CORE))
s->packet |= DCA_PACKET_XLL | DCA_PACKET_RECOVERY;
else if (ret == AVERROR(ENOMEM) || (avctx->err_recognition & AV_EF_EXPLODE))
return ret;
} else {
s->packet |= DCA_PACKET_XLL;
}
}
// Parse LBR component in EXSS
if (asset && (asset->extension_mask & DCA_EXSS_LBR)) {
if ((ret = ff_dca_lbr_parse(&s->lbr, input, asset)) < 0) {
if (ret == AVERROR(ENOMEM) || (avctx->err_recognition & AV_EF_EXPLODE))
return ret;
} else {
s->packet |= DCA_PACKET_LBR;
}
}
// Parse core extensions in EXSS or backward compatible core sub-stream
if ((s->packet & DCA_PACKET_CORE)
&& (ret = ff_dca_core_parse_exss(&s->core, input, asset)) < 0)
return ret;
}
// Filter the frame
if (s->packet & DCA_PACKET_LBR) {
if ((ret = ff_dca_lbr_filter_frame(&s->lbr, frame)) < 0)
return ret;
} else if (s->packet & DCA_PACKET_XLL) {
if (s->packet & DCA_PACKET_CORE) {
int x96_synth = -1;
// Enable X96 synthesis if needed
if (s->xll.chset[0].freq == 96000 && s->core.sample_rate == 48000)
x96_synth = 1;
if ((ret = ff_dca_core_filter_fixed(&s->core, x96_synth)) < 0)
return ret;
// Force lossy downmixed output on the first core frame filtered.
// This prevents audible clicks when seeking and is consistent with
// what reference decoder does when there are multiple channel sets.
if (!(prev_packet & DCA_PACKET_RESIDUAL) && s->xll.nreschsets > 0
&& s->xll.nchsets > 1) {
av_log(avctx, AV_LOG_VERBOSE, "Forcing XLL recovery mode\n");
s->packet |= DCA_PACKET_RECOVERY;
}
// Set 'residual ok' flag for the next frame
s->packet |= DCA_PACKET_RESIDUAL;
}
if ((ret = ff_dca_xll_filter_frame(&s->xll, frame)) < 0) {
// Fall back to core unless hard error
if (!(s->packet & DCA_PACKET_CORE))
return ret;
if (ret != AVERROR_INVALIDDATA || (avctx->err_recognition & AV_EF_EXPLODE))
return ret;
if ((ret = ff_dca_core_filter_frame(&s->core, frame)) < 0)
return ret;
}
} else if (s->packet & DCA_PACKET_CORE) {
if ((ret = ff_dca_core_filter_frame(&s->core, frame)) < 0)
return ret;
if (s->core.filter_mode & DCA_FILTER_MODE_FIXED)
s->packet |= DCA_PACKET_RESIDUAL;
} else {
av_log(avctx, AV_LOG_ERROR, "No valid DCA sub-stream found\n");
if (s->core_only)
av_log(avctx, AV_LOG_WARNING, "Consider disabling 'core_only' option\n");
return AVERROR_INVALIDDATA;
}
*got_frame_ptr = 1;
return avpkt->size;
}