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ffmpeg/libavcodec/dvdec.c

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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/internal.h"
#include "libavutil/pixdesc.h"
#include "avcodec.h"
#include "internal.h"
#include "get_bits.h"
#include "put_bits.h"
#include "simple_idct.h"
#include "dvdata.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, int line_size, int16_t *block);
uint8_t partial_bit_count;
uint32_t partial_bit_buffer;
int shift_offset;
} BlockInfo;
static const int dv_iweight_bits = 14;
/* 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(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 (;;) {
av_dlog(NULL, "%2d: bits=%04x index=%d\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;
av_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));
}
}
/* 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 + FF_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */
LOCAL_ALIGNED_16(uint8_t, vs_bit_buffer, [5*80 + FF_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */
const int log2_blocksize = 3-s->avctx->lowres;
int is_field_mode[5];
av_assert1((((int)mb_bit_buffer) & 7) == 0);
av_assert1((((int)vs_bit_buffer) & 7) == 0);
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;
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->sys->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->sys->idct_factor[(class1 == 3)*2*22*64 + dct_mode*22*64 +
(quant + ff_dv_quant_offset[class1])*64];
}
dc = dc << 2;
/* 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;
av_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);
block += 64;
mb++;
}
/* pass 2: we can do it just after */
av_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;
}
}
/* 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 */
av_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) {
av_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);
block += 64;
mb++;
}
}
/* 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->picture.linesize[0] << ((!is_field_mode[mb_index]) * log2_blocksize));
} else {
y_stride = (2 << log2_blocksize);
}
y_ptr = s->picture.data[0] + ((mb_y * s->picture.linesize[0] + mb_x) << log2_blocksize);
linesize = s->picture.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->picture.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->picture.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->picture.linesize[j], pixels += 8) {
ptr1 = pixels + (1 << (log2_blocksize - 1));
c_ptr1 = c_ptr + (s->picture.linesize[j] << log2_blocksize);
for (x = 0; x < (1 << (log2_blocksize - 1)); x++) {
c_ptr[x] = pixels[x];
c_ptr1[x] = ptr1[x];
}
}
block += 64; mb++;
} else {
y_stride = (mb_y == 134) ? (1 << log2_blocksize) :
s->picture.linesize[j] << ((!is_field_mode[mb_index]) * log2_blocksize);
linesize = s->picture.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;
const uint8_t* vsc_pack;
int apt, is16_9;
s->sys = avpriv_dv_frame_profile2(avctx, s->sys, buf, buf_size);
if (!s->sys || buf_size < s->sys->frame_size || ff_dv_init_dynamic_tables(s->sys)) {
av_log(avctx, AV_LOG_ERROR, "could not find dv frame profile\n");
return -1; /* NOTE: we only accept several full frames */
}
if (s->picture.data[0])
avctx->release_buffer(avctx, &s->picture);
avcodec_get_frame_defaults(&s->picture);
s->picture.reference = 0;
s->picture.key_frame = 1;
s->picture.pict_type = AV_PICTURE_TYPE_I;
avctx->pix_fmt = s->sys->pix_fmt;
avctx->time_base = s->sys->time_base;
avcodec_set_dimensions(avctx, s->sys->width, s->sys->height);
if (ff_get_buffer(avctx, &s->picture) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return -1;
}
s->picture.interlaced_frame = 1;
s->picture.top_field_first = 0;
/* Determine the codec's sample_aspect ratio and field order 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);
avctx->sample_aspect_ratio = s->sys->sar[is16_9];
s->picture.top_field_first = !(vsc_pack[3] & 0x40);
}
s->buf = buf;
avctx->execute(avctx, dv_decode_video_segment, s->sys->work_chunks, NULL,
dv_work_pool_size(s->sys), sizeof(DVwork_chunk));
emms_c();
/* return image */
*got_frame = 1;
*(AVFrame*)data = s->picture;
return s->sys->frame_size;
}
static int dvvideo_close(AVCodecContext *c)
{
DVVideoContext *s = c->priv_data;
if (s->picture.data[0])
c->release_buffer(c, &s->picture);
return 0;
}
AVCodec ff_dvvideo_decoder = {
.name = "dvvideo",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_DVVIDEO,
.priv_data_size = sizeof(DVVideoContext),
.init = ff_dvvideo_init,
.close = dvvideo_close,
.decode = dvvideo_decode_frame,
.capabilities = CODEC_CAP_DR1 | CODEC_CAP_SLICE_THREADS,
.max_lowres = 3,
.long_name = NULL_IF_CONFIG_SMALL("DV (Digital Video)"),
};
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