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ffmpeg/libavcodec/dvdec.c
Andreas Rheinhardt a247ac640d avcodec: Constify AVCodecs 
Given that the AVCodec.next pointer has now been removed, most of the
AVCodecs are not modified at all any more and can therefore be made
const (as this patch does); the only exceptions are the very few codecs
for external libraries that have a init_static_data callback.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
2021-04-27 10:43:15 -03:00

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/*
* DV decoder
* Copyright (c) 2002 Fabrice Bellard
* Copyright (c) 2004 Roman Shaposhnik
*
* 50 Mbps (DVCPRO50) support
* Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>
*
* 100 Mbps (DVCPRO HD) support
* Initial code by Daniel Maas <dmaas@maasdigital.com> (funded by BBC R&D)
* Final code by Roman Shaposhnik
*
* Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
* of DV technical info.
*
* 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
*/
/**
* @file
* DV decoder
*/
#include "libavutil/avassert.h"
#include "libavutil/imgutils.h"
#include "libavutil/internal.h"
#include "libavutil/mem_internal.h"
#include "libavutil/pixdesc.h"
#include "avcodec.h"
#include "dv.h"
#include "dv_profile_internal.h"
#include "dvdata.h"
#include "get_bits.h"
#include "internal.h"
#include "put_bits.h"
#include "simple_idct.h"
#include "thread.h"
typedef struct BlockInfo {
const uint32_t *factor_table;
const uint8_t *scan_table;
uint8_t pos; /* position in block */
void (*idct_put)(uint8_t *dest, ptrdiff_t stride, int16_t *block);
uint8_t partial_bit_count;
uint32_t partial_bit_buffer;
int shift_offset;
} BlockInfo;
static const int dv_iweight_bits = 14;
static const uint16_t dv_iweight_88[64] = {
32768, 16705, 16705, 17734, 17032, 17734, 18205, 18081,
18081, 18205, 18725, 18562, 19195, 18562, 18725, 19266,
19091, 19705, 19705, 19091, 19266, 21407, 19643, 20267,
20228, 20267, 19643, 21407, 22725, 21826, 20853, 20806,
20806, 20853, 21826, 22725, 23170, 23170, 21407, 21400,
21407, 23170, 23170, 24598, 23786, 22018, 22018, 23786,
24598, 25251, 24465, 22654, 24465, 25251, 25972, 25172,
25172, 25972, 26722, 27969, 26722, 29692, 29692, 31521,
};
static const uint16_t dv_iweight_248[64] = {
32768, 16384, 16705, 16705, 17734, 17734, 17734, 17734,
18081, 18081, 18725, 18725, 21407, 21407, 19091, 19091,
19195, 19195, 18205, 18205, 18725, 18725, 19705, 19705,
20267, 20267, 21826, 21826, 23170, 23170, 20806, 20806,
20267, 20267, 19266, 19266, 21407, 21407, 20853, 20853,
21400, 21400, 23786, 23786, 24465, 24465, 22018, 22018,
23170, 23170, 22725, 22725, 24598, 24598, 24465, 24465,
25172, 25172, 27969, 27969, 25972, 25972, 29692, 29692
};
/**
* The "inverse" DV100 weights are actually just the spec weights (zig-zagged).
*/
static const uint16_t dv_iweight_1080_y[64] = {
128, 16, 16, 17, 17, 17, 18, 18,
18, 18, 18, 18, 19, 18, 18, 19,
19, 19, 19, 19, 19, 42, 38, 40,
40, 40, 38, 42, 44, 43, 41, 41,
41, 41, 43, 44, 45, 45, 42, 42,
42, 45, 45, 48, 46, 43, 43, 46,
48, 49, 48, 44, 48, 49, 101, 98,
98, 101, 104, 109, 104, 116, 116, 123,
};
static const uint16_t dv_iweight_1080_c[64] = {
128, 16, 16, 17, 17, 17, 25, 25,
25, 25, 26, 25, 26, 25, 26, 26,
26, 27, 27, 26, 26, 42, 38, 40,
40, 40, 38, 42, 44, 43, 41, 41,
41, 41, 43, 44, 91, 91, 84, 84,
84, 91, 91, 96, 93, 86, 86, 93,
96, 197, 191, 177, 191, 197, 203, 197,
197, 203, 209, 219, 209, 232, 232, 246,
};
static const uint16_t dv_iweight_720_y[64] = {
128, 16, 16, 17, 17, 17, 18, 18,
18, 18, 18, 18, 19, 18, 18, 19,
19, 19, 19, 19, 19, 42, 38, 40,
40, 40, 38, 42, 44, 43, 41, 41,
41, 41, 43, 44, 68, 68, 63, 63,
63, 68, 68, 96, 92, 86, 86, 92,
96, 98, 96, 88, 96, 98, 202, 196,
196, 202, 208, 218, 208, 232, 232, 246,
};
static const uint16_t dv_iweight_720_c[64] = {
128, 24, 24, 26, 26, 26, 36, 36,
36, 36, 36, 36, 38, 36, 36, 38,
38, 38, 38, 38, 38, 84, 76, 80,
80, 80, 76, 84, 88, 86, 82, 82,
82, 82, 86, 88, 182, 182, 168, 168,
168, 182, 182, 192, 186, 192, 172, 186,
192, 394, 382, 354, 382, 394, 406, 394,
394, 406, 418, 438, 418, 464, 464, 492,
};
static void dv_init_weight_tables(DVVideoContext *ctx, const AVDVProfile *d)
{
int j, i, c, s;
uint32_t *factor1 = &ctx->idct_factor[0],
*factor2 = &ctx->idct_factor[DV_PROFILE_IS_HD(d) ? 4096 : 2816];
if (DV_PROFILE_IS_HD(d)) {
/* quantization quanta by QNO for DV100 */
static const uint8_t dv100_qstep[16] = {
1, /* QNO = 0 and 1 both have no quantization */
1,
2, 3, 4, 5, 6, 7, 8, 16, 18, 20, 22, 24, 28, 52
};
const uint16_t *iweight1, *iweight2;
if (d->height == 720) {
iweight1 = &dv_iweight_720_y[0];
iweight2 = &dv_iweight_720_c[0];
} else {
iweight1 = &dv_iweight_1080_y[0];
iweight2 = &dv_iweight_1080_c[0];
}
for (c = 0; c < 4; c++) {
for (s = 0; s < 16; s++) {
for (i = 0; i < 64; i++) {
*factor1++ = (dv100_qstep[s] << (c + 9)) * iweight1[i];
*factor2++ = (dv100_qstep[s] << (c + 9)) * iweight2[i];
}
}
}
} else {
static const uint8_t dv_quant_areas[4] = { 6, 21, 43, 64 };
const uint16_t *iweight1 = &dv_iweight_88[0];
for (j = 0; j < 2; j++, iweight1 = &dv_iweight_248[0]) {
for (s = 0; s < 22; s++) {
for (i = c = 0; c < 4; c++) {
for (; i < dv_quant_areas[c]; i++) {
*factor1 = iweight1[i] << (ff_dv_quant_shifts[s][c] + 1);
*factor2++ = (*factor1++) << 1;
}
}
}
}
}
}
static av_cold int dvvideo_decode_init(AVCodecContext *avctx)
{
DVVideoContext *s = avctx->priv_data;
int i;
ff_idctdsp_init(&s->idsp, avctx);
for (i = 0; i < 64; i++)
s->dv_zigzag[0][i] = s->idsp.idct_permutation[ff_zigzag_direct[i]];
if (avctx->lowres){
for (i = 0; i < 64; i++){
int j = ff_dv_zigzag248_direct[i];
s->dv_zigzag[1][i] = s->idsp.idct_permutation[(j & 7) + (j & 8) * 4 + (j & 48) / 2];
}
}else
memcpy(s->dv_zigzag[1], ff_dv_zigzag248_direct, sizeof(s->dv_zigzag[1]));
s->idct_put[0] = s->idsp.idct_put;
s->idct_put[1] = ff_simple_idct248_put;
return ff_dvvideo_init(avctx);
}
/* decode AC coefficients */
static void dv_decode_ac(GetBitContext *gb, BlockInfo *mb, int16_t *block)
{
int last_index = gb->size_in_bits;
const uint8_t *scan_table = mb->scan_table;
const uint32_t *factor_table = mb->factor_table;
int pos = mb->pos;
int partial_bit_count = mb->partial_bit_count;
int level, run, vlc_len, index;
OPEN_READER_NOSIZE(re, gb);
UPDATE_CACHE(re, gb);
/* if we must parse a partial VLC, we do it here */
if (partial_bit_count > 0) {
re_cache = re_cache >> partial_bit_count |
mb->partial_bit_buffer;
re_index -= partial_bit_count;
mb->partial_bit_count = 0;
}
/* get the AC coefficients until last_index is reached */
for (;;) {
ff_dlog(NULL, "%2d: bits=%04"PRIx32" index=%u\n",
pos, SHOW_UBITS(re, gb, 16), re_index);
/* our own optimized GET_RL_VLC */
index = NEG_USR32(re_cache, TEX_VLC_BITS);
vlc_len = ff_dv_rl_vlc[index].len;
if (vlc_len < 0) {
index = NEG_USR32((unsigned) re_cache << TEX_VLC_BITS, -vlc_len) +
ff_dv_rl_vlc[index].level;
vlc_len = TEX_VLC_BITS - vlc_len;
}
level = ff_dv_rl_vlc[index].level;
run = ff_dv_rl_vlc[index].run;
/* gotta check if we're still within gb boundaries */
if (re_index + vlc_len > last_index) {
/* should be < 16 bits otherwise a codeword could have been parsed */
mb->partial_bit_count = last_index - re_index;
mb->partial_bit_buffer = re_cache & ~(-1u >> mb->partial_bit_count);
re_index = last_index;
break;
}
re_index += vlc_len;
ff_dlog(NULL, "run=%d level=%d\n", run, level);
pos += run;
if (pos >= 64)
break;
level = (level * factor_table[pos] + (1 << (dv_iweight_bits - 1))) >>
dv_iweight_bits;
block[scan_table[pos]] = level;
UPDATE_CACHE(re, gb);
}
CLOSE_READER(re, gb);
mb->pos = pos;
}
static inline void bit_copy(PutBitContext *pb, GetBitContext *gb)
{
int bits_left = get_bits_left(gb);
while (bits_left >= MIN_CACHE_BITS) {
put_bits(pb, MIN_CACHE_BITS, get_bits(gb, MIN_CACHE_BITS));
bits_left -= MIN_CACHE_BITS;
}
if (bits_left > 0)
put_bits(pb, bits_left, get_bits(gb, bits_left));
}
static av_always_inline void put_block_8x4(int16_t *block, uint8_t *av_restrict p, int stride)
{
int i, j;
for (i = 0; i < 4; i++) {
for (j = 0; j < 8; j++)
p[j] = av_clip_uint8(block[j]);
block += 8;
p += stride;
}
}
static void dv100_idct_put_last_row_field_chroma(DVVideoContext *s, uint8_t *data,
int stride, int16_t *blocks)
{
s->idsp.idct(blocks + 0*64);
s->idsp.idct(blocks + 1*64);
put_block_8x4(blocks+0*64, data, stride<<1);
put_block_8x4(blocks+0*64 + 4*8, data + 8, stride<<1);
put_block_8x4(blocks+1*64, data + stride, stride<<1);
put_block_8x4(blocks+1*64 + 4*8, data + 8 + stride, stride<<1);
}
static void dv100_idct_put_last_row_field_luma(DVVideoContext *s, uint8_t *data,
int stride, int16_t *blocks)
{
s->idsp.idct(blocks + 0*64);
s->idsp.idct(blocks + 1*64);
s->idsp.idct(blocks + 2*64);
s->idsp.idct(blocks + 3*64);
put_block_8x4(blocks+0*64, data, stride<<1);
put_block_8x4(blocks+0*64 + 4*8, data + 16, stride<<1);
put_block_8x4(blocks+1*64, data + 8, stride<<1);
put_block_8x4(blocks+1*64 + 4*8, data + 24, stride<<1);
put_block_8x4(blocks+2*64, data + stride, stride<<1);
put_block_8x4(blocks+2*64 + 4*8, data + 16 + stride, stride<<1);
put_block_8x4(blocks+3*64, data + 8 + stride, stride<<1);
put_block_8x4(blocks+3*64 + 4*8, data + 24 + stride, stride<<1);
}
/* mb_x and mb_y are in units of 8 pixels */
static int dv_decode_video_segment(AVCodecContext *avctx, void *arg)
{
DVVideoContext *s = avctx->priv_data;
DVwork_chunk *work_chunk = arg;
int quant, dc, dct_mode, class1, j;
int mb_index, mb_x, mb_y, last_index;
int y_stride, linesize;
int16_t *block, *block1;
int c_offset;
uint8_t *y_ptr;
const uint8_t *buf_ptr;
PutBitContext pb, vs_pb;
GetBitContext gb;
BlockInfo mb_data[5 * DV_MAX_BPM], *mb, *mb1;
LOCAL_ALIGNED_16(int16_t, sblock, [5 * DV_MAX_BPM], [64]);
LOCAL_ALIGNED_16(uint8_t, mb_bit_buffer, [80 + AV_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */
LOCAL_ALIGNED_16(uint8_t, vs_bit_buffer, [80 * 5 + AV_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */
const int log2_blocksize = 3-s->avctx->lowres;
int is_field_mode[5];
int vs_bit_buffer_damaged = 0;
int mb_bit_buffer_damaged[5] = {0};
int retried = 0;
int sta;
av_assert1((((int) mb_bit_buffer) & 7) == 0);
av_assert1((((int) vs_bit_buffer) & 7) == 0);
retry:
memset(sblock, 0, 5 * DV_MAX_BPM * sizeof(*sblock));
/* pass 1: read DC and AC coefficients in blocks */
buf_ptr = &s->buf[work_chunk->buf_offset * 80];
block1 = &sblock[0][0];
mb1 = mb_data;
init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80);
for (mb_index = 0; mb_index < 5; mb_index++, mb1 += s->sys->bpm, block1 += s->sys->bpm * 64) {
/* skip header */
quant = buf_ptr[3] & 0x0f;
if (avctx->error_concealment) {
if ((buf_ptr[3] >> 4) == 0x0E)
vs_bit_buffer_damaged = 1;
if (!mb_index) {
sta = buf_ptr[3] >> 4;
} else if (sta != (buf_ptr[3] >> 4))
vs_bit_buffer_damaged = 1;
}
buf_ptr += 4;
init_put_bits(&pb, mb_bit_buffer, 80);
mb = mb1;
block = block1;
is_field_mode[mb_index] = 0;
for (j = 0; j < s->sys->bpm; j++) {
last_index = s->sys->block_sizes[j];
init_get_bits(&gb, buf_ptr, last_index);
/* get the DC */
dc = get_sbits(&gb, 9);
dct_mode = get_bits1(&gb);
class1 = get_bits(&gb, 2);
if (DV_PROFILE_IS_HD(s->sys)) {
mb->idct_put = s->idct_put[0];
mb->scan_table = s->dv_zigzag[0];
mb->factor_table = &s->idct_factor[(j >= 4) * 4 * 16 * 64 +
class1 * 16 * 64 +
quant * 64];
is_field_mode[mb_index] |= !j && dct_mode;
} else {
mb->idct_put = s->idct_put[dct_mode && log2_blocksize == 3];
mb->scan_table = s->dv_zigzag[dct_mode];
mb->factor_table =
&s->idct_factor[(class1 == 3) * 2 * 22 * 64 +
dct_mode * 22 * 64 +
(quant + ff_dv_quant_offset[class1]) * 64];
}
dc = dc * 4;
/* convert to unsigned because 128 is not added in the
* standard IDCT */
dc += 1024;
block[0] = dc;
buf_ptr += last_index >> 3;
mb->pos = 0;
mb->partial_bit_count = 0;
ff_dlog(avctx, "MB block: %d, %d ", mb_index, j);
dv_decode_ac(&gb, mb, block);
/* write the remaining bits in a new buffer only if the
* block is finished */
if (mb->pos >= 64)
bit_copy(&pb, &gb);
if (mb->pos >= 64 && mb->pos < 127)
vs_bit_buffer_damaged = mb_bit_buffer_damaged[mb_index] = 1;
block += 64;
mb++;
}
if (mb_bit_buffer_damaged[mb_index] > 0)
continue;
/* pass 2: we can do it just after */
ff_dlog(avctx, "***pass 2 size=%d MB#=%d\n", put_bits_count(&pb), mb_index);
block = block1;
mb = mb1;
init_get_bits(&gb, mb_bit_buffer, put_bits_count(&pb));
put_bits32(&pb, 0); // padding must be zeroed
flush_put_bits(&pb);
for (j = 0; j < s->sys->bpm; j++, block += 64, mb++) {
if (mb->pos < 64 && get_bits_left(&gb) > 0) {
dv_decode_ac(&gb, mb, block);
/* if still not finished, no need to parse other blocks */
if (mb->pos < 64)
break;
if (mb->pos < 127)
vs_bit_buffer_damaged = mb_bit_buffer_damaged[mb_index] = 1;
}
}
/* all blocks are finished, so the extra bytes can be used at
* the video segment level */
if (j >= s->sys->bpm)
bit_copy(&vs_pb, &gb);
}
/* we need a pass over the whole video segment */
ff_dlog(avctx, "***pass 3 size=%d\n", put_bits_count(&vs_pb));
block = &sblock[0][0];
mb = mb_data;
init_get_bits(&gb, vs_bit_buffer, put_bits_count(&vs_pb));
put_bits32(&vs_pb, 0); // padding must be zeroed
flush_put_bits(&vs_pb);
for (mb_index = 0; mb_index < 5; mb_index++) {
for (j = 0; j < s->sys->bpm; j++) {
if (mb->pos < 64 && get_bits_left(&gb) > 0 && !vs_bit_buffer_damaged) {
ff_dlog(avctx, "start %d:%d\n", mb_index, j);
dv_decode_ac(&gb, mb, block);
}
if (mb->pos >= 64 && mb->pos < 127) {
av_log(avctx, AV_LOG_ERROR,
"AC EOB marker is absent pos=%d\n", mb->pos);
vs_bit_buffer_damaged = 1;
}
block += 64;
mb++;
}
}
if (vs_bit_buffer_damaged && !retried) {
av_log(avctx, AV_LOG_ERROR, "Concealing bitstream errors\n");
retried = 1;
goto retry;
}
/* compute idct and place blocks */
block = &sblock[0][0];
mb = mb_data;
for (mb_index = 0; mb_index < 5; mb_index++) {
dv_calculate_mb_xy(s, work_chunk, mb_index, &mb_x, &mb_y);
/* idct_put'ting luminance */
if ((s->sys->pix_fmt == AV_PIX_FMT_YUV420P) ||
(s->sys->pix_fmt == AV_PIX_FMT_YUV411P && mb_x >= (704 / 8)) ||
(s->sys->height >= 720 && mb_y != 134)) {
y_stride = (s->frame->linesize[0] <<
((!is_field_mode[mb_index]) * log2_blocksize));
} else {
y_stride = (2 << log2_blocksize);
}
y_ptr = s->frame->data[0] +
((mb_y * s->frame->linesize[0] + mb_x) << log2_blocksize);
if (mb_y == 134 && is_field_mode[mb_index]) {
dv100_idct_put_last_row_field_luma(s, y_ptr, s->frame->linesize[0], block);
} else {
linesize = s->frame->linesize[0] << is_field_mode[mb_index];
mb[0].idct_put(y_ptr, linesize, block + 0 * 64);
if (s->sys->video_stype == 4) { /* SD 422 */
mb[2].idct_put(y_ptr + (1 << log2_blocksize), linesize, block + 2 * 64);
} else {
mb[1].idct_put(y_ptr + (1 << log2_blocksize), linesize, block + 1 * 64);
mb[2].idct_put(y_ptr + y_stride, linesize, block + 2 * 64);
mb[3].idct_put(y_ptr + (1 << log2_blocksize) + y_stride, linesize, block + 3 * 64);
}
}
mb += 4;
block += 4 * 64;
/* idct_put'ting chrominance */
c_offset = (((mb_y >> (s->sys->pix_fmt == AV_PIX_FMT_YUV420P)) * s->frame->linesize[1] +
(mb_x >> ((s->sys->pix_fmt == AV_PIX_FMT_YUV411P) ? 2 : 1))) << log2_blocksize);
for (j = 2; j; j--) {
uint8_t *c_ptr = s->frame->data[j] + c_offset;
if (s->sys->pix_fmt == AV_PIX_FMT_YUV411P && mb_x >= (704 / 8)) {
uint64_t aligned_pixels[64 / 8];
uint8_t *pixels = (uint8_t *) aligned_pixels;
uint8_t *c_ptr1, *ptr1;
int x, y;
mb->idct_put(pixels, 8, block);
for (y = 0; y < (1 << log2_blocksize); y++, c_ptr += s->frame->linesize[j], pixels += 8) {
ptr1 = pixels + ((1 << (log2_blocksize))>>1);
c_ptr1 = c_ptr + (s->frame->linesize[j] << log2_blocksize);
for (x = 0; x < (1 << FFMAX(log2_blocksize - 1, 0)); x++) {
c_ptr[x] = pixels[x];
c_ptr1[x] = ptr1[x];
}
}
block += 64;
mb++;
} else {
y_stride = (mb_y == 134) ? (1 << log2_blocksize) :
s->frame->linesize[j] << ((!is_field_mode[mb_index]) * log2_blocksize);
if (mb_y == 134 && is_field_mode[mb_index]) {
dv100_idct_put_last_row_field_chroma(s, c_ptr, s->frame->linesize[j], block);
mb += 2;
block += 2*64;
} else {
linesize = s->frame->linesize[j] << is_field_mode[mb_index];
(mb++)->idct_put(c_ptr, linesize, block);
block += 64;
if (s->sys->bpm == 8) {
(mb++)->idct_put(c_ptr + y_stride, linesize, block);
block += 64;
}
}
}
}
}
return 0;
}
/* NOTE: exactly one frame must be given (120000 bytes for NTSC,
* 144000 bytes for PAL - or twice those for 50Mbps) */
static int dvvideo_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame, AVPacket *avpkt)
{
uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
DVVideoContext *s = avctx->priv_data;
ThreadFrame frame = { .f = data };
const uint8_t *vsc_pack;
int apt, is16_9, ret;
const AVDVProfile *sys;
sys = ff_dv_frame_profile(avctx, s->sys, buf, buf_size);
if (!sys || buf_size < sys->frame_size) {
av_log(avctx, AV_LOG_ERROR, "could not find dv frame profile\n");
return -1; /* NOTE: we only accept several full frames */
}
if (sys != s->sys) {
ret = ff_dv_init_dynamic_tables(s, sys);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Error initializing the work tables.\n");
return ret;
}
dv_init_weight_tables(s, sys);
s->sys = sys;
}
s->frame = frame.f;
frame.f->key_frame = 1;
frame.f->pict_type = AV_PICTURE_TYPE_I;
avctx->pix_fmt = s->sys->pix_fmt;
avctx->framerate = av_inv_q(s->sys->time_base);
ret = ff_set_dimensions(avctx, s->sys->width, s->sys->height);
if (ret < 0)
return ret;
/* Determine the codec's sample_aspect ratio from the packet */
vsc_pack = buf + 80 * 5 + 48 + 5;
if (*vsc_pack == dv_video_control) {
apt = buf[4] & 0x07;
is16_9 = (vsc_pack[2] & 0x07) == 0x02 ||
(!apt && (vsc_pack[2] & 0x07) == 0x07);
ff_set_sar(avctx, s->sys->sar[is16_9]);
}
if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
return ret;
/* Determine the codec's field order from the packet */
if ( *vsc_pack == dv_video_control ) {
if (avctx->height == 720) {
frame.f->interlaced_frame = 0;
frame.f->top_field_first = 0;
} else if (avctx->height == 1080) {
frame.f->interlaced_frame = 1;
frame.f->top_field_first = (vsc_pack[3] & 0x40) == 0x40;
} else {
frame.f->interlaced_frame = (vsc_pack[3] & 0x10) == 0x10;
frame.f->top_field_first = !(vsc_pack[3] & 0x40);
}
}
s->buf = buf;
avctx->execute(avctx, dv_decode_video_segment, s->work_chunks, NULL,
dv_work_pool_size(s->sys), sizeof(DVwork_chunk));
emms_c();
/* return image */
*got_frame = 1;
return s->sys->frame_size;
}
const AVCodec ff_dvvideo_decoder = {
.name = "dvvideo",
.long_name = NULL_IF_CONFIG_SMALL("DV (Digital Video)"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_DVVIDEO,
.priv_data_size = sizeof(DVVideoContext),
.init = dvvideo_decode_init,
.decode = dvvideo_decode_frame,
.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS | AV_CODEC_CAP_SLICE_THREADS,
.max_lowres = 3,
};
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