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FFmpeg/libavcodec/rv40.c
2013-03-08 07:38:30 +01:00

577 lines
23 KiB
C

/*
* RV40 decoder
* Copyright (c) 2007 Konstantin Shishkov
*
* This file is part of Libav.
*
* 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.
*
* 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* RV40 decoder
*/
#include "libavutil/imgutils.h"
#include "avcodec.h"
#include "mpegvideo.h"
#include "golomb.h"
#include "rv34.h"
#include "rv40vlc2.h"
#include "rv40data.h"
static VLC aic_top_vlc;
static VLC aic_mode1_vlc[AIC_MODE1_NUM], aic_mode2_vlc[AIC_MODE2_NUM];
static VLC ptype_vlc[NUM_PTYPE_VLCS], btype_vlc[NUM_BTYPE_VLCS];
static const int16_t mode2_offs[] = {
0, 614, 1222, 1794, 2410, 3014, 3586, 4202, 4792, 5382, 5966, 6542,
7138, 7716, 8292, 8864, 9444, 10030, 10642, 11212, 11814
};
/**
* Initialize all tables.
*/
static av_cold void rv40_init_tables(void)
{
int i;
static VLC_TYPE aic_table[1 << AIC_TOP_BITS][2];
static VLC_TYPE aic_mode1_table[AIC_MODE1_NUM << AIC_MODE1_BITS][2];
static VLC_TYPE aic_mode2_table[11814][2];
static VLC_TYPE ptype_table[NUM_PTYPE_VLCS << PTYPE_VLC_BITS][2];
static VLC_TYPE btype_table[NUM_BTYPE_VLCS << BTYPE_VLC_BITS][2];
aic_top_vlc.table = aic_table;
aic_top_vlc.table_allocated = 1 << AIC_TOP_BITS;
init_vlc(&aic_top_vlc, AIC_TOP_BITS, AIC_TOP_SIZE,
rv40_aic_top_vlc_bits, 1, 1,
rv40_aic_top_vlc_codes, 1, 1, INIT_VLC_USE_NEW_STATIC);
for(i = 0; i < AIC_MODE1_NUM; i++){
// Every tenth VLC table is empty
if((i % 10) == 9) continue;
aic_mode1_vlc[i].table = &aic_mode1_table[i << AIC_MODE1_BITS];
aic_mode1_vlc[i].table_allocated = 1 << AIC_MODE1_BITS;
init_vlc(&aic_mode1_vlc[i], AIC_MODE1_BITS, AIC_MODE1_SIZE,
aic_mode1_vlc_bits[i], 1, 1,
aic_mode1_vlc_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
}
for(i = 0; i < AIC_MODE2_NUM; i++){
aic_mode2_vlc[i].table = &aic_mode2_table[mode2_offs[i]];
aic_mode2_vlc[i].table_allocated = mode2_offs[i + 1] - mode2_offs[i];
init_vlc(&aic_mode2_vlc[i], AIC_MODE2_BITS, AIC_MODE2_SIZE,
aic_mode2_vlc_bits[i], 1, 1,
aic_mode2_vlc_codes[i], 2, 2, INIT_VLC_USE_NEW_STATIC);
}
for(i = 0; i < NUM_PTYPE_VLCS; i++){
ptype_vlc[i].table = &ptype_table[i << PTYPE_VLC_BITS];
ptype_vlc[i].table_allocated = 1 << PTYPE_VLC_BITS;
ff_init_vlc_sparse(&ptype_vlc[i], PTYPE_VLC_BITS, PTYPE_VLC_SIZE,
ptype_vlc_bits[i], 1, 1,
ptype_vlc_codes[i], 1, 1,
ptype_vlc_syms, 1, 1, INIT_VLC_USE_NEW_STATIC);
}
for(i = 0; i < NUM_BTYPE_VLCS; i++){
btype_vlc[i].table = &btype_table[i << BTYPE_VLC_BITS];
btype_vlc[i].table_allocated = 1 << BTYPE_VLC_BITS;
ff_init_vlc_sparse(&btype_vlc[i], BTYPE_VLC_BITS, BTYPE_VLC_SIZE,
btype_vlc_bits[i], 1, 1,
btype_vlc_codes[i], 1, 1,
btype_vlc_syms, 1, 1, INIT_VLC_USE_NEW_STATIC);
}
}
/**
* Get stored dimension from bitstream.
*
* If the width/height is the standard one then it's coded as a 3-bit index.
* Otherwise it is coded as escaped 8-bit portions.
*/
static int get_dimension(GetBitContext *gb, const int *dim)
{
int t = get_bits(gb, 3);
int val = dim[t];
if(val < 0)
val = dim[get_bits1(gb) - val];
if(!val){
do{
t = get_bits(gb, 8);
val += t << 2;
}while(t == 0xFF);
}
return val;
}
/**
* Get encoded picture size - usually this is called from rv40_parse_slice_header.
*/
static void rv40_parse_picture_size(GetBitContext *gb, int *w, int *h)
{
*w = get_dimension(gb, rv40_standard_widths);
*h = get_dimension(gb, rv40_standard_heights);
}
static int rv40_parse_slice_header(RV34DecContext *r, GetBitContext *gb, SliceInfo *si)
{
int mb_bits;
int w = r->s.width, h = r->s.height;
int mb_size;
memset(si, 0, sizeof(SliceInfo));
if(get_bits1(gb))
return -1;
si->type = get_bits(gb, 2);
if(si->type == 1) si->type = 0;
si->quant = get_bits(gb, 5);
if(get_bits(gb, 2))
return -1;
si->vlc_set = get_bits(gb, 2);
skip_bits1(gb);
si->pts = get_bits(gb, 13);
if(!si->type || !get_bits1(gb))
rv40_parse_picture_size(gb, &w, &h);
if(av_image_check_size(w, h, 0, r->s.avctx) < 0)
return -1;
si->width = w;
si->height = h;
mb_size = ((w + 15) >> 4) * ((h + 15) >> 4);
mb_bits = ff_rv34_get_start_offset(gb, mb_size);
si->start = get_bits(gb, mb_bits);
return 0;
}
/**
* Decode 4x4 intra types array.
*/
static int rv40_decode_intra_types(RV34DecContext *r, GetBitContext *gb, int8_t *dst)
{
MpegEncContext *s = &r->s;
int i, j, k, v;
int A, B, C;
int pattern;
int8_t *ptr;
for(i = 0; i < 4; i++, dst += r->intra_types_stride){
if(!i && s->first_slice_line){
pattern = get_vlc2(gb, aic_top_vlc.table, AIC_TOP_BITS, 1);
dst[0] = (pattern >> 2) & 2;
dst[1] = (pattern >> 1) & 2;
dst[2] = pattern & 2;
dst[3] = (pattern << 1) & 2;
continue;
}
ptr = dst;
for(j = 0; j < 4; j++){
/* Coefficients are read using VLC chosen by the prediction pattern
* The first one (used for retrieving a pair of coefficients) is
* constructed from the top, top right and left coefficients
* The second one (used for retrieving only one coefficient) is
* top + 10 * left.
*/
A = ptr[-r->intra_types_stride + 1]; // it won't be used for the last coefficient in a row
B = ptr[-r->intra_types_stride];
C = ptr[-1];
pattern = A + (B << 4) + (C << 8);
for(k = 0; k < MODE2_PATTERNS_NUM; k++)
if(pattern == rv40_aic_table_index[k])
break;
if(j < 3 && k < MODE2_PATTERNS_NUM){ //pattern is found, decoding 2 coefficients
v = get_vlc2(gb, aic_mode2_vlc[k].table, AIC_MODE2_BITS, 2);
*ptr++ = v/9;
*ptr++ = v%9;
j++;
}else{
if(B != -1 && C != -1)
v = get_vlc2(gb, aic_mode1_vlc[B + C*10].table, AIC_MODE1_BITS, 1);
else{ // tricky decoding
v = 0;
switch(C){
case -1: // code 0 -> 1, 1 -> 0
if(B < 2)
v = get_bits1(gb) ^ 1;
break;
case 0:
case 2: // code 0 -> 2, 1 -> 0
v = (get_bits1(gb) ^ 1) << 1;
break;
}
}
*ptr++ = v;
}
}
}
return 0;
}
/**
* Decode macroblock information.
*/
static int rv40_decode_mb_info(RV34DecContext *r)
{
MpegEncContext *s = &r->s;
GetBitContext *gb = &s->gb;
int q, i;
int prev_type = 0;
int mb_pos = s->mb_x + s->mb_y * s->mb_stride;
if(!r->s.mb_skip_run)
r->s.mb_skip_run = svq3_get_ue_golomb(gb) + 1;
if(--r->s.mb_skip_run)
return RV34_MB_SKIP;
if(r->avail_cache[6-4]){
int blocks[RV34_MB_TYPES] = {0};
int count = 0;
if(r->avail_cache[6-1])
blocks[r->mb_type[mb_pos - 1]]++;
blocks[r->mb_type[mb_pos - s->mb_stride]]++;
if(r->avail_cache[6-2])
blocks[r->mb_type[mb_pos - s->mb_stride + 1]]++;
if(r->avail_cache[6-5])
blocks[r->mb_type[mb_pos - s->mb_stride - 1]]++;
for(i = 0; i < RV34_MB_TYPES; i++){
if(blocks[i] > count){
count = blocks[i];
prev_type = i;
if(count>1)
break;
}
}
} else if (r->avail_cache[6-1])
prev_type = r->mb_type[mb_pos - 1];
if(s->pict_type == AV_PICTURE_TYPE_P){
prev_type = block_num_to_ptype_vlc_num[prev_type];
q = get_vlc2(gb, ptype_vlc[prev_type].table, PTYPE_VLC_BITS, 1);
if(q < PBTYPE_ESCAPE)
return q;
q = get_vlc2(gb, ptype_vlc[prev_type].table, PTYPE_VLC_BITS, 1);
av_log(s->avctx, AV_LOG_ERROR, "Dquant for P-frame\n");
}else{
prev_type = block_num_to_btype_vlc_num[prev_type];
q = get_vlc2(gb, btype_vlc[prev_type].table, BTYPE_VLC_BITS, 1);
if(q < PBTYPE_ESCAPE)
return q;
q = get_vlc2(gb, btype_vlc[prev_type].table, BTYPE_VLC_BITS, 1);
av_log(s->avctx, AV_LOG_ERROR, "Dquant for B-frame\n");
}
return 0;
}
enum RV40BlockPos{
POS_CUR,
POS_TOP,
POS_LEFT,
POS_BOTTOM,
};
#define MASK_CUR 0x0001
#define MASK_RIGHT 0x0008
#define MASK_BOTTOM 0x0010
#define MASK_TOP 0x1000
#define MASK_Y_TOP_ROW 0x000F
#define MASK_Y_LAST_ROW 0xF000
#define MASK_Y_LEFT_COL 0x1111
#define MASK_Y_RIGHT_COL 0x8888
#define MASK_C_TOP_ROW 0x0003
#define MASK_C_LAST_ROW 0x000C
#define MASK_C_LEFT_COL 0x0005
#define MASK_C_RIGHT_COL 0x000A
static const int neighbour_offs_x[4] = { 0, 0, -1, 0 };
static const int neighbour_offs_y[4] = { 0, -1, 0, 1 };
static void rv40_adaptive_loop_filter(RV34DSPContext *rdsp,
uint8_t *src, int stride, int dmode,
int lim_q1, int lim_p1,
int alpha, int beta, int beta2,
int chroma, int edge, int dir)
{
int filter_p1, filter_q1;
int strong;
int lims;
strong = rdsp->rv40_loop_filter_strength[dir](src, stride, beta, beta2,
edge, &filter_p1, &filter_q1);
lims = filter_p1 + filter_q1 + ((lim_q1 + lim_p1) >> 1) + 1;
if (strong) {
rdsp->rv40_strong_loop_filter[dir](src, stride, alpha,
lims, dmode, chroma);
} else if (filter_p1 & filter_q1) {
rdsp->rv40_weak_loop_filter[dir](src, stride, 1, 1, alpha, beta,
lims, lim_q1, lim_p1);
} else if (filter_p1 | filter_q1) {
rdsp->rv40_weak_loop_filter[dir](src, stride, filter_p1, filter_q1,
alpha, beta, lims >> 1, lim_q1 >> 1,
lim_p1 >> 1);
}
}
/**
* RV40 loop filtering function
*/
static void rv40_loop_filter(RV34DecContext *r, int row)
{
MpegEncContext *s = &r->s;
int mb_pos, mb_x;
int i, j, k;
uint8_t *Y, *C;
int alpha, beta, betaY, betaC;
int q;
int mbtype[4]; ///< current macroblock and its neighbours types
/**
* flags indicating that macroblock can be filtered with strong filter
* it is set only for intra coded MB and MB with DCs coded separately
*/
int mb_strong[4];
int clip[4]; ///< MB filter clipping value calculated from filtering strength
/**
* coded block patterns for luma part of current macroblock and its neighbours
* Format:
* LSB corresponds to the top left block,
* each nibble represents one row of subblocks.
*/
int cbp[4];
/**
* coded block patterns for chroma part of current macroblock and its neighbours
* Format is the same as for luma with two subblocks in a row.
*/
int uvcbp[4][2];
/**
* This mask represents the pattern of luma subblocks that should be filtered
* in addition to the coded ones because because they lie at the edge of
* 8x8 block with different enough motion vectors
*/
unsigned mvmasks[4];
mb_pos = row * s->mb_stride;
for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
int mbtype = s->current_picture_ptr->mb_type[mb_pos];
if(IS_INTRA(mbtype) || IS_SEPARATE_DC(mbtype))
r->cbp_luma [mb_pos] = r->deblock_coefs[mb_pos] = 0xFFFF;
if(IS_INTRA(mbtype))
r->cbp_chroma[mb_pos] = 0xFF;
}
mb_pos = row * s->mb_stride;
for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
int y_h_deblock, y_v_deblock;
int c_v_deblock[2], c_h_deblock[2];
int clip_left;
int avail[4];
unsigned y_to_deblock;
int c_to_deblock[2];
q = s->current_picture_ptr->qscale_table[mb_pos];
alpha = rv40_alpha_tab[q];
beta = rv40_beta_tab [q];
betaY = betaC = beta * 3;
if(s->width * s->height <= 176*144)
betaY += beta;
avail[0] = 1;
avail[1] = row;
avail[2] = mb_x;
avail[3] = row < s->mb_height - 1;
for(i = 0; i < 4; i++){
if(avail[i]){
int pos = mb_pos + neighbour_offs_x[i] + neighbour_offs_y[i]*s->mb_stride;
mvmasks[i] = r->deblock_coefs[pos];
mbtype [i] = s->current_picture_ptr->mb_type[pos];
cbp [i] = r->cbp_luma[pos];
uvcbp[i][0] = r->cbp_chroma[pos] & 0xF;
uvcbp[i][1] = r->cbp_chroma[pos] >> 4;
}else{
mvmasks[i] = 0;
mbtype [i] = mbtype[0];
cbp [i] = 0;
uvcbp[i][0] = uvcbp[i][1] = 0;
}
mb_strong[i] = IS_INTRA(mbtype[i]) || IS_SEPARATE_DC(mbtype[i]);
clip[i] = rv40_filter_clip_tbl[mb_strong[i] + 1][q];
}
y_to_deblock = mvmasks[POS_CUR]
| (mvmasks[POS_BOTTOM] << 16);
/* This pattern contains bits signalling that horizontal edges of
* the current block can be filtered.
* That happens when either of adjacent subblocks is coded or lies on
* the edge of 8x8 blocks with motion vectors differing by more than
* 3/4 pel in any component (any edge orientation for some reason).
*/
y_h_deblock = y_to_deblock
| ((cbp[POS_CUR] << 4) & ~MASK_Y_TOP_ROW)
| ((cbp[POS_TOP] & MASK_Y_LAST_ROW) >> 12);
/* This pattern contains bits signalling that vertical edges of
* the current block can be filtered.
* That happens when either of adjacent subblocks is coded or lies on
* the edge of 8x8 blocks with motion vectors differing by more than
* 3/4 pel in any component (any edge orientation for some reason).
*/
y_v_deblock = y_to_deblock
| ((cbp[POS_CUR] << 1) & ~MASK_Y_LEFT_COL)
| ((cbp[POS_LEFT] & MASK_Y_RIGHT_COL) >> 3);
if(!mb_x)
y_v_deblock &= ~MASK_Y_LEFT_COL;
if(!row)
y_h_deblock &= ~MASK_Y_TOP_ROW;
if(row == s->mb_height - 1 || (mb_strong[POS_CUR] | mb_strong[POS_BOTTOM]))
y_h_deblock &= ~(MASK_Y_TOP_ROW << 16);
/* Calculating chroma patterns is similar and easier since there is
* no motion vector pattern for them.
*/
for(i = 0; i < 2; i++){
c_to_deblock[i] = (uvcbp[POS_BOTTOM][i] << 4) | uvcbp[POS_CUR][i];
c_v_deblock[i] = c_to_deblock[i]
| ((uvcbp[POS_CUR] [i] << 1) & ~MASK_C_LEFT_COL)
| ((uvcbp[POS_LEFT][i] & MASK_C_RIGHT_COL) >> 1);
c_h_deblock[i] = c_to_deblock[i]
| ((uvcbp[POS_TOP][i] & MASK_C_LAST_ROW) >> 2)
| (uvcbp[POS_CUR][i] << 2);
if(!mb_x)
c_v_deblock[i] &= ~MASK_C_LEFT_COL;
if(!row)
c_h_deblock[i] &= ~MASK_C_TOP_ROW;
if(row == s->mb_height - 1 || (mb_strong[POS_CUR] | mb_strong[POS_BOTTOM]))
c_h_deblock[i] &= ~(MASK_C_TOP_ROW << 4);
}
for(j = 0; j < 16; j += 4){
Y = s->current_picture_ptr->f.data[0] + mb_x*16 + (row*16 + j) * s->linesize;
for(i = 0; i < 4; i++, Y += 4){
int ij = i + j;
int clip_cur = y_to_deblock & (MASK_CUR << ij) ? clip[POS_CUR] : 0;
int dither = j ? ij : i*4;
// if bottom block is coded then we can filter its top edge
// (or bottom edge of this block, which is the same)
if(y_h_deblock & (MASK_BOTTOM << ij)){
rv40_adaptive_loop_filter(&r->rdsp, Y+4*s->linesize,
s->linesize, dither,
y_to_deblock & (MASK_BOTTOM << ij) ? clip[POS_CUR] : 0,
clip_cur, alpha, beta, betaY,
0, 0, 0);
}
// filter left block edge in ordinary mode (with low filtering strength)
if(y_v_deblock & (MASK_CUR << ij) && (i || !(mb_strong[POS_CUR] | mb_strong[POS_LEFT]))){
if(!i)
clip_left = mvmasks[POS_LEFT] & (MASK_RIGHT << j) ? clip[POS_LEFT] : 0;
else
clip_left = y_to_deblock & (MASK_CUR << (ij-1)) ? clip[POS_CUR] : 0;
rv40_adaptive_loop_filter(&r->rdsp, Y, s->linesize, dither,
clip_cur,
clip_left,
alpha, beta, betaY, 0, 0, 1);
}
// filter top edge of the current macroblock when filtering strength is high
if(!j && y_h_deblock & (MASK_CUR << i) && (mb_strong[POS_CUR] | mb_strong[POS_TOP])){
rv40_adaptive_loop_filter(&r->rdsp, Y, s->linesize, dither,
clip_cur,
mvmasks[POS_TOP] & (MASK_TOP << i) ? clip[POS_TOP] : 0,
alpha, beta, betaY, 0, 1, 0);
}
// filter left block edge in edge mode (with high filtering strength)
if(y_v_deblock & (MASK_CUR << ij) && !i && (mb_strong[POS_CUR] | mb_strong[POS_LEFT])){
clip_left = mvmasks[POS_LEFT] & (MASK_RIGHT << j) ? clip[POS_LEFT] : 0;
rv40_adaptive_loop_filter(&r->rdsp, Y, s->linesize, dither,
clip_cur,
clip_left,
alpha, beta, betaY, 0, 1, 1);
}
}
}
for(k = 0; k < 2; k++){
for(j = 0; j < 2; j++){
C = s->current_picture_ptr->f.data[k + 1] + mb_x*8 + (row*8 + j*4) * s->uvlinesize;
for(i = 0; i < 2; i++, C += 4){
int ij = i + j*2;
int clip_cur = c_to_deblock[k] & (MASK_CUR << ij) ? clip[POS_CUR] : 0;
if(c_h_deblock[k] & (MASK_CUR << (ij+2))){
int clip_bot = c_to_deblock[k] & (MASK_CUR << (ij+2)) ? clip[POS_CUR] : 0;
rv40_adaptive_loop_filter(&r->rdsp, C+4*s->uvlinesize, s->uvlinesize, i*8,
clip_bot,
clip_cur,
alpha, beta, betaC, 1, 0, 0);
}
if((c_v_deblock[k] & (MASK_CUR << ij)) && (i || !(mb_strong[POS_CUR] | mb_strong[POS_LEFT]))){
if(!i)
clip_left = uvcbp[POS_LEFT][k] & (MASK_CUR << (2*j+1)) ? clip[POS_LEFT] : 0;
else
clip_left = c_to_deblock[k] & (MASK_CUR << (ij-1)) ? clip[POS_CUR] : 0;
rv40_adaptive_loop_filter(&r->rdsp, C, s->uvlinesize, j*8,
clip_cur,
clip_left,
alpha, beta, betaC, 1, 0, 1);
}
if(!j && c_h_deblock[k] & (MASK_CUR << ij) && (mb_strong[POS_CUR] | mb_strong[POS_TOP])){
int clip_top = uvcbp[POS_TOP][k] & (MASK_CUR << (ij+2)) ? clip[POS_TOP] : 0;
rv40_adaptive_loop_filter(&r->rdsp, C, s->uvlinesize, i*8,
clip_cur,
clip_top,
alpha, beta, betaC, 1, 1, 0);
}
if(c_v_deblock[k] & (MASK_CUR << ij) && !i && (mb_strong[POS_CUR] | mb_strong[POS_LEFT])){
clip_left = uvcbp[POS_LEFT][k] & (MASK_CUR << (2*j+1)) ? clip[POS_LEFT] : 0;
rv40_adaptive_loop_filter(&r->rdsp, C, s->uvlinesize, j*8,
clip_cur,
clip_left,
alpha, beta, betaC, 1, 1, 1);
}
}
}
}
}
}
/**
* Initialize decoder.
*/
static av_cold int rv40_decode_init(AVCodecContext *avctx)
{
RV34DecContext *r = avctx->priv_data;
r->rv30 = 0;
ff_rv34_decode_init(avctx);
if(!aic_top_vlc.bits)
rv40_init_tables();
r->parse_slice_header = rv40_parse_slice_header;
r->decode_intra_types = rv40_decode_intra_types;
r->decode_mb_info = rv40_decode_mb_info;
r->loop_filter = rv40_loop_filter;
r->luma_dc_quant_i = rv40_luma_dc_quant[0];
r->luma_dc_quant_p = rv40_luma_dc_quant[1];
return 0;
}
AVCodec ff_rv40_decoder = {
.name = "rv40",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_RV40,
.priv_data_size = sizeof(RV34DecContext),
.init = rv40_decode_init,
.close = ff_rv34_decode_end,
.decode = ff_rv34_decode_frame,
.capabilities = CODEC_CAP_DR1 | CODEC_CAP_DELAY |
CODEC_CAP_FRAME_THREADS,
.flush = ff_mpeg_flush,
.long_name = NULL_IF_CONFIG_SMALL("RealVideo 4.0"),
.pix_fmts = ff_pixfmt_list_420,
.init_thread_copy = ONLY_IF_THREADS_ENABLED(ff_rv34_decode_init_thread_copy),
.update_thread_context = ONLY_IF_THREADS_ENABLED(ff_rv34_decode_update_thread_context),
};