mirror of https://github.com/FFmpeg/FFmpeg.git
Paul B Mahol
6 years ago
parent
fa08345e88
commit
0279cb4f69
7 changed files with 193 additions and 1 deletions
@ -0,0 +1,184 @@ |
||||
/*
|
||||
* Copyright (c) 2018 Paul B Mahol |
||||
* |
||||
* This file is part of FFmpeg. |
||||
* |
||||
* FFmpeg 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, |
||||
* 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 |
||||
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
||||
*/ |
||||
|
||||
#include "avcodec.h" |
||||
#include "bsf.h" |
||||
#include "get_bits.h" |
||||
#include "mlp_parser.h" |
||||
#include "mlp.h" |
||||
|
||||
typedef struct AccessUnit { |
||||
uint8_t bits[4]; |
||||
uint16_t offset; |
||||
uint16_t optional; |
||||
} AccessUnit; |
||||
|
||||
typedef struct TrueHDCoreContext { |
||||
const AVClass *class; |
||||
|
||||
MLPHeaderInfo hdr; |
||||
} TrueHDCoreContext; |
||||
|
||||
static int truehd_core_filter(AVBSFContext *ctx, AVPacket *out) |
||||
{ |
||||
TrueHDCoreContext *s = ctx->priv_data; |
||||
GetBitContext gbc; |
||||
AccessUnit units[MAX_SUBSTREAMS]; |
||||
AVPacket *in; |
||||
int ret, i, size, last_offset = 0; |
||||
int in_size, out_size; |
||||
int have_header = 0; |
||||
int substream_bits = 0; |
||||
int start, end; |
||||
uint16_t dts; |
||||
|
||||
ret = ff_bsf_get_packet(ctx, &in); |
||||
if (ret < 0) |
||||
return ret; |
||||
|
||||
if (in->size < 4) |
||||
goto fail; |
||||
|
||||
ret = init_get_bits(&gbc, in->data, 32); |
||||
if (ret < 0) |
||||
goto fail; |
||||
|
||||
skip_bits(&gbc, 4); |
||||
in_size = get_bits(&gbc, 12) * 2; |
||||
if (in_size < 4 || in_size > in->size) |
||||
goto fail; |
||||
|
||||
out_size = in_size; |
||||
dts = get_bits(&gbc, 16); |
||||
|
||||
ret = init_get_bits8(&gbc, in->data + 4, in->size - 4); |
||||
if (ret < 0) |
||||
goto fail; |
||||
|
||||
if (show_bits_long(&gbc, 32) == 0xf8726fba) { |
||||
if ((ret = ff_mlp_read_major_sync(ctx, &s->hdr, &gbc)) != 0) |
||||
goto fail; |
||||
have_header = 1; |
||||
} |
||||
|
||||
if (s->hdr.num_substreams > MAX_SUBSTREAMS) |
||||
goto fail; |
||||
|
||||
start = get_bits_count(&gbc); |
||||
for (i = 0; i < s->hdr.num_substreams; i++) { |
||||
for (int j = 0; j < 4; j++) |
||||
units[i].bits[j] = get_bits1(&gbc); |
||||
|
||||
units[i].offset = get_bits(&gbc, 12) * 2; |
||||
if (i < FFMIN(s->hdr.num_substreams, 3)) { |
||||
last_offset = units[i].offset; |
||||
substream_bits += 16; |
||||
} |
||||
|
||||
if (units[i].bits[0]) { |
||||
units[i].optional = get_bits(&gbc, 16); |
||||
if (i < FFMIN(s->hdr.num_substreams, 3)) |
||||
substream_bits += 16; |
||||
} |
||||
} |
||||
end = get_bits_count(&gbc); |
||||
|
||||
size = ((end + 7) >> 3) + 4 + last_offset; |
||||
if (size >= 0 && size <= in->size) |
||||
out_size = size; |
||||
if (out_size < in_size) { |
||||
int bpos = 0, reduce = (end - start - substream_bits) >> 4; |
||||
uint16_t parity_nibble = 0; |
||||
uint16_t auheader; |
||||
|
||||
ret = av_new_packet(out, out_size); |
||||
if (ret < 0) |
||||
goto fail; |
||||
|
||||
AV_WB16(out->data + 2, dts); |
||||
parity_nibble = dts; |
||||
out->size -= reduce * 2; |
||||
parity_nibble ^= out->size / 2; |
||||
|
||||
if (have_header) { |
||||
memcpy(out->data + 4, in->data + 4, 28); |
||||
out->data[16 + 4] = (out->data[16 + 4] & 0x0f) | (FFMIN(s->hdr.num_substreams, 3) << 4); |
||||
out->data[25 + 4] = out->data[25 + 4] & 0xfe; |
||||
out->data[26 + 4] = 0xff; |
||||
out->data[27 + 4] = 0xff; |
||||
AV_WL16(out->data + 4 + 26, ff_mlp_checksum16(out->data + 4, 26)); |
||||
} |
||||
|
||||
for (i = 0; i < FFMIN(s->hdr.num_substreams, 3); i++) { |
||||
uint16_t substr_hdr = 0; |
||||
|
||||
substr_hdr |= (units[i].bits[0] << 15); |
||||
substr_hdr |= (units[i].bits[1] << 14); |
||||
substr_hdr |= (units[i].bits[2] << 13); |
||||
substr_hdr |= (units[i].bits[3] << 12); |
||||
substr_hdr |= (units[i].offset / 2) & 0x0FFF; |
||||
|
||||
AV_WB16(out->data + have_header * 28 + 4 + bpos, substr_hdr); |
||||
|
||||
parity_nibble ^= out->data[have_header * 28 + 4 + bpos++]; |
||||
parity_nibble ^= out->data[have_header * 28 + 4 + bpos++]; |
||||
|
||||
if (units[i].bits[0]) { |
||||
AV_WB16(out->data + have_header * 28 + 4 + bpos, units[i].optional); |
||||
|
||||
parity_nibble ^= out->data[have_header * 28 + 4 + bpos++]; |
||||
parity_nibble ^= out->data[have_header * 28 + 4 + bpos++]; |
||||
} |
||||
} |
||||
|
||||
parity_nibble ^= parity_nibble >> 8; |
||||
parity_nibble ^= parity_nibble >> 4; |
||||
parity_nibble &= 0xF; |
||||
|
||||
memcpy(out->data + have_header * 28 + 4 + bpos, |
||||
in->data + 4 + (end >> 3), |
||||
out_size - (4 + (end >> 3))); |
||||
auheader = (parity_nibble ^ 0xF) << 12; |
||||
auheader |= (out->size / 2) & 0x0fff; |
||||
AV_WB16(out->data, auheader); |
||||
|
||||
ret = av_packet_copy_props(out, in); |
||||
} else { |
||||
av_packet_move_ref(out, in); |
||||
} |
||||
|
||||
fail: |
||||
if (ret < 0) |
||||
av_packet_unref(out); |
||||
av_packet_free(&in); |
||||
|
||||
return ret; |
||||
} |
||||
|
||||
static const enum AVCodecID codec_ids[] = { |
||||
AV_CODEC_ID_TRUEHD, AV_CODEC_ID_NONE, |
||||
}; |
||||
|
||||
const AVBitStreamFilter ff_truehd_core_bsf = { |
||||
.name = "truehd_core", |
||||
.priv_data_size = sizeof(TrueHDCoreContext), |
||||
.filter = truehd_core_filter, |
||||
.codec_ids = codec_ids, |
||||
}; |
||||
Loading…
Reference in new issue