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FFmpeg/libavcodec/h264_refs.c

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/*
* H.26L/H.264/AVC/JVT/14496-10/... reference picture handling
* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
*
* 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
* H.264 / AVC / MPEG4 part10 reference picture handling.
* @author Michael Niedermayer <michaelni@gmx.at>
*/
#include "internal.h"
#include "dsputil.h"
#include "avcodec.h"
#include "h264.h"
#include "golomb.h"
//#undef NDEBUG
#include <assert.h>
static void pic_as_field(Picture *pic, const int parity){
int i;
for (i = 0; i < 4; ++i) {
if (parity == PICT_BOTTOM_FIELD)
pic->data[i] += pic->linesize[i];
pic->reference = parity;
pic->linesize[i] *= 2;
}
pic->poc= pic->field_poc[parity == PICT_BOTTOM_FIELD];
}
static int split_field_copy(Picture *dest, Picture *src,
int parity, int id_add){
int match = !!(src->reference & parity);
if (match) {
*dest = *src;
if(parity != PICT_FRAME){
pic_as_field(dest, parity);
dest->pic_id *= 2;
dest->pic_id += id_add;
}
}
return match;
}
static int build_def_list(Picture *def, Picture **in, int len, int is_long, int sel){
int i[2]={0};
int index=0;
while(i[0]<len || i[1]<len){
while(i[0]<len && !(in[ i[0] ] && (in[ i[0] ]->reference & sel)))
i[0]++;
while(i[1]<len && !(in[ i[1] ] && (in[ i[1] ]->reference & (sel^3))))
i[1]++;
if(i[0] < len){
in[ i[0] ]->pic_id= is_long ? i[0] : in[ i[0] ]->frame_num;
split_field_copy(&def[index++], in[ i[0]++ ], sel , 1);
}
if(i[1] < len){
in[ i[1] ]->pic_id= is_long ? i[1] : in[ i[1] ]->frame_num;
split_field_copy(&def[index++], in[ i[1]++ ], sel^3, 0);
}
}
return index;
}
static int add_sorted(Picture **sorted, Picture **src, int len, int limit, int dir){
int i, best_poc;
int out_i= 0;
for(;;){
best_poc= dir ? INT_MIN : INT_MAX;
for(i=0; i<len; i++){
const int poc= src[i]->poc;
if(((poc > limit) ^ dir) && ((poc < best_poc) ^ dir)){
best_poc= poc;
sorted[out_i]= src[i];
}
}
if(best_poc == (dir ? INT_MIN : INT_MAX))
break;
limit= sorted[out_i++]->poc - dir;
}
return out_i;
}
int ff_h264_fill_default_ref_list(H264Context *h){
MpegEncContext * const s = &h->s;
int i, len;
if(h->slice_type_nos==FF_B_TYPE){
Picture *sorted[32];
int cur_poc, list;
int lens[2];
if(FIELD_PICTURE)
cur_poc= s->current_picture_ptr->field_poc[ s->picture_structure == PICT_BOTTOM_FIELD ];
else
cur_poc= s->current_picture_ptr->poc;
for(list= 0; list<2; list++){
len= add_sorted(sorted , h->short_ref, h->short_ref_count, cur_poc, 1^list);
len+=add_sorted(sorted+len, h->short_ref, h->short_ref_count, cur_poc, 0^list);
assert(len<=32);
len= build_def_list(h->default_ref_list[list] , sorted , len, 0, s->picture_structure);
len+=build_def_list(h->default_ref_list[list]+len, h->long_ref, 16 , 1, s->picture_structure);
assert(len<=32);
if(len < h->ref_count[list])
memset(&h->default_ref_list[list][len], 0, sizeof(Picture)*(h->ref_count[list] - len));
lens[list]= len;
}
if(lens[0] == lens[1] && lens[1] > 1){
for(i=0; h->default_ref_list[0][i].data[0] == h->default_ref_list[1][i].data[0] && i<lens[0]; i++);
if(i == lens[0])
FFSWAP(Picture, h->default_ref_list[1][0], h->default_ref_list[1][1]);
}
}else{
len = build_def_list(h->default_ref_list[0] , h->short_ref, h->short_ref_count, 0, s->picture_structure);
len+= build_def_list(h->default_ref_list[0]+len, h-> long_ref, 16 , 1, s->picture_structure);
assert(len <= 32);
if(len < h->ref_count[0])
memset(&h->default_ref_list[0][len], 0, sizeof(Picture)*(h->ref_count[0] - len));
}
#ifdef TRACE
for (i=0; i<h->ref_count[0]; i++) {
tprintf(h->s.avctx, "List0: %s fn:%d 0x%p\n", (h->default_ref_list[0][i].long_ref ? "LT" : "ST"), h->default_ref_list[0][i].pic_id, h->default_ref_list[0][i].data[0]);
}
if(h->slice_type_nos==FF_B_TYPE){
for (i=0; i<h->ref_count[1]; i++) {
tprintf(h->s.avctx, "List1: %s fn:%d 0x%p\n", (h->default_ref_list[1][i].long_ref ? "LT" : "ST"), h->default_ref_list[1][i].pic_id, h->default_ref_list[1][i].data[0]);
}
}
#endif
return 0;
}
static void print_short_term(H264Context *h);
static void print_long_term(H264Context *h);
/**
* Extract structure information about the picture described by pic_num in
* the current decoding context (frame or field). Note that pic_num is
* picture number without wrapping (so, 0<=pic_num<max_pic_num).
* @param pic_num picture number for which to extract structure information
* @param structure one of PICT_XXX describing structure of picture
* with pic_num
* @return frame number (short term) or long term index of picture
* described by pic_num
*/
static int pic_num_extract(H264Context *h, int pic_num, int *structure){
MpegEncContext * const s = &h->s;
*structure = s->picture_structure;
if(FIELD_PICTURE){
if (!(pic_num & 1))
/* opposite field */
*structure ^= PICT_FRAME;
pic_num >>= 1;
}
return pic_num;
}
int ff_h264_decode_ref_pic_list_reordering(H264Context *h){
MpegEncContext * const s = &h->s;
int list, index, pic_structure;
print_short_term(h);
print_long_term(h);
for(list=0; list<h->list_count; list++){
memcpy(h->ref_list[list], h->default_ref_list[list], sizeof(Picture)*h->ref_count[list]);
if(get_bits1(&s->gb)){
int pred= h->curr_pic_num;
for(index=0; ; index++){
unsigned int reordering_of_pic_nums_idc= get_ue_golomb_31(&s->gb);
unsigned int pic_id;
int i;
Picture *ref = NULL;
if(reordering_of_pic_nums_idc==3)
break;
if(index >= h->ref_count[list]){
av_log(h->s.avctx, AV_LOG_ERROR, "reference count overflow\n");
return -1;
}
if(reordering_of_pic_nums_idc<3){
if(reordering_of_pic_nums_idc<2){
const unsigned int abs_diff_pic_num= get_ue_golomb(&s->gb) + 1;
int frame_num;
if(abs_diff_pic_num > h->max_pic_num){
av_log(h->s.avctx, AV_LOG_ERROR, "abs_diff_pic_num overflow\n");
return -1;
}
if(reordering_of_pic_nums_idc == 0) pred-= abs_diff_pic_num;
else pred+= abs_diff_pic_num;
pred &= h->max_pic_num - 1;
frame_num = pic_num_extract(h, pred, &pic_structure);
for(i= h->short_ref_count-1; i>=0; i--){
ref = h->short_ref[i];
assert(ref->reference);
assert(!ref->long_ref);
if(
ref->frame_num == frame_num &&
(ref->reference & pic_structure)
)
break;
}
if(i>=0)
ref->pic_id= pred;
}else{
int long_idx;
pic_id= get_ue_golomb(&s->gb); //long_term_pic_idx
long_idx= pic_num_extract(h, pic_id, &pic_structure);
if(long_idx>31){
av_log(h->s.avctx, AV_LOG_ERROR, "long_term_pic_idx overflow\n");
return -1;
}
ref = h->long_ref[long_idx];
assert(!(ref && !ref->reference));
if(ref && (ref->reference & pic_structure)){
ref->pic_id= pic_id;
assert(ref->long_ref);
i=0;
}else{
i=-1;
}
}
if (i < 0) {
av_log(h->s.avctx, AV_LOG_ERROR, "reference picture missing during reorder\n");
memset(&h->ref_list[list][index], 0, sizeof(Picture)); //FIXME
} else {
for(i=index; i+1<h->ref_count[list]; i++){
if(ref->long_ref == h->ref_list[list][i].long_ref && ref->pic_id == h->ref_list[list][i].pic_id)
break;
}
for(; i > index; i--){
h->ref_list[list][i]= h->ref_list[list][i-1];
}
h->ref_list[list][index]= *ref;
if (FIELD_PICTURE){
pic_as_field(&h->ref_list[list][index], pic_structure);
}
}
}else{
av_log(h->s.avctx, AV_LOG_ERROR, "illegal reordering_of_pic_nums_idc\n");
return -1;
}
}
}
}
for(list=0; list<h->list_count; list++){
for(index= 0; index < h->ref_count[list]; index++){
if(!h->ref_list[list][index].data[0]){
av_log(h->s.avctx, AV_LOG_ERROR, "Missing reference picture\n");
if(h->default_ref_list[list][0].data[0])
h->ref_list[list][index]= h->default_ref_list[list][0];
else
return -1;
}
}
}
return 0;
}
void ff_h264_fill_mbaff_ref_list(H264Context *h){
int list, i, j;
for(list=0; list<2; list++){ //FIXME try list_count
for(i=0; i<h->ref_count[list]; i++){
Picture *frame = &h->ref_list[list][i];
Picture *field = &h->ref_list[list][16+2*i];
field[0] = *frame;
for(j=0; j<3; j++)
field[0].linesize[j] <<= 1;
field[0].reference = PICT_TOP_FIELD;
field[0].poc= field[0].field_poc[0];
field[1] = field[0];
for(j=0; j<3; j++)
field[1].data[j] += frame->linesize[j];
field[1].reference = PICT_BOTTOM_FIELD;
field[1].poc= field[1].field_poc[1];
h->luma_weight[16+2*i][list][0] = h->luma_weight[16+2*i+1][list][0] = h->luma_weight[i][list][0];
h->luma_weight[16+2*i][list][1] = h->luma_weight[16+2*i+1][list][1] = h->luma_weight[i][list][1];
for(j=0; j<2; j++){
h->chroma_weight[16+2*i][list][j][0] = h->chroma_weight[16+2*i+1][list][j][0] = h->chroma_weight[i][list][j][0];
h->chroma_weight[16+2*i][list][j][1] = h->chroma_weight[16+2*i+1][list][j][1] = h->chroma_weight[i][list][j][1];
}
}
}
}
/**
* Mark a picture as no longer needed for reference. The refmask
* argument allows unreferencing of individual fields or the whole frame.
* If the picture becomes entirely unreferenced, but is being held for
* display purposes, it is marked as such.
* @param refmask mask of fields to unreference; the mask is bitwise
* anded with the reference marking of pic
* @return non-zero if pic becomes entirely unreferenced (except possibly
* for display purposes) zero if one of the fields remains in
* reference
*/
static inline int unreference_pic(H264Context *h, Picture *pic, int refmask){
int i;
if (pic->reference &= refmask) {
return 0;
} else {
for(i = 0; h->delayed_pic[i]; i++)
if(pic == h->delayed_pic[i]){
pic->reference=DELAYED_PIC_REF;
break;
}
return 1;
}
}
/**
* Find a Picture in the short term reference list by frame number.
* @param frame_num frame number to search for
* @param idx the index into h->short_ref where returned picture is found
* undefined if no picture found.
* @return pointer to the found picture, or NULL if no pic with the provided
* frame number is found
*/
static Picture * find_short(H264Context *h, int frame_num, int *idx){
MpegEncContext * const s = &h->s;
int i;
for(i=0; i<h->short_ref_count; i++){
Picture *pic= h->short_ref[i];
if(s->avctx->debug&FF_DEBUG_MMCO)
av_log(h->s.avctx, AV_LOG_DEBUG, "%d %d %p\n", i, pic->frame_num, pic);
if(pic->frame_num == frame_num) {
*idx = i;
return pic;
}
}
return NULL;
}
/**
* Remove a picture from the short term reference list by its index in
* that list. This does no checking on the provided index; it is assumed
* to be valid. Other list entries are shifted down.
* @param i index into h->short_ref of picture to remove.
*/
static void remove_short_at_index(H264Context *h, int i){
assert(i >= 0 && i < h->short_ref_count);
h->short_ref[i]= NULL;
if (--h->short_ref_count)
memmove(&h->short_ref[i], &h->short_ref[i+1], (h->short_ref_count - i)*sizeof(Picture*));
}
/**
*
* @return the removed picture or NULL if an error occurs
*/
static Picture * remove_short(H264Context *h, int frame_num, int ref_mask){
MpegEncContext * const s = &h->s;
Picture *pic;
int i;
if(s->avctx->debug&FF_DEBUG_MMCO)
av_log(h->s.avctx, AV_LOG_DEBUG, "remove short %d count %d\n", frame_num, h->short_ref_count);
pic = find_short(h, frame_num, &i);
if (pic){
if(unreference_pic(h, pic, ref_mask))
remove_short_at_index(h, i);
}
return pic;
}
/**
* Remove a picture from the long term reference list by its index in
* that list.
* @return the removed picture or NULL if an error occurs
*/
static Picture * remove_long(H264Context *h, int i, int ref_mask){
Picture *pic;
pic= h->long_ref[i];
if (pic){
if(unreference_pic(h, pic, ref_mask)){
assert(h->long_ref[i]->long_ref == 1);
h->long_ref[i]->long_ref= 0;
h->long_ref[i]= NULL;
h->long_ref_count--;
}
}
return pic;
}
void ff_h264_remove_all_refs(H264Context *h){
int i;
for(i=0; i<16; i++){
remove_long(h, i, 0);
}
assert(h->long_ref_count==0);
for(i=0; i<h->short_ref_count; i++){
unreference_pic(h, h->short_ref[i], 0);
h->short_ref[i]= NULL;
}
h->short_ref_count=0;
}
/**
* print short term list
*/
static void print_short_term(H264Context *h) {
uint32_t i;
if(h->s.avctx->debug&FF_DEBUG_MMCO) {
av_log(h->s.avctx, AV_LOG_DEBUG, "short term list:\n");
for(i=0; i<h->short_ref_count; i++){
Picture *pic= h->short_ref[i];
av_log(h->s.avctx, AV_LOG_DEBUG, "%d fn:%d poc:%d %p\n", i, pic->frame_num, pic->poc, pic->data[0]);
}
}
}
/**
* print long term list
*/
static void print_long_term(H264Context *h) {
uint32_t i;
if(h->s.avctx->debug&FF_DEBUG_MMCO) {
av_log(h->s.avctx, AV_LOG_DEBUG, "long term list:\n");
for(i = 0; i < 16; i++){
Picture *pic= h->long_ref[i];
if (pic) {
av_log(h->s.avctx, AV_LOG_DEBUG, "%d fn:%d poc:%d %p\n", i, pic->frame_num, pic->poc, pic->data[0]);
}
}
}
}
int ff_h264_execute_ref_pic_marking(H264Context *h, MMCO *mmco, int mmco_count){
MpegEncContext * const s = &h->s;
int i, av_uninit(j);
int current_ref_assigned=0;
Picture *av_uninit(pic);
if((s->avctx->debug&FF_DEBUG_MMCO) && mmco_count==0)
av_log(h->s.avctx, AV_LOG_DEBUG, "no mmco here\n");
for(i=0; i<mmco_count; i++){
int av_uninit(structure), av_uninit(frame_num);
if(s->avctx->debug&FF_DEBUG_MMCO)
av_log(h->s.avctx, AV_LOG_DEBUG, "mmco:%d %d %d\n", h->mmco[i].opcode, h->mmco[i].short_pic_num, h->mmco[i].long_arg);
if( mmco[i].opcode == MMCO_SHORT2UNUSED
|| mmco[i].opcode == MMCO_SHORT2LONG){
frame_num = pic_num_extract(h, mmco[i].short_pic_num, &structure);
pic = find_short(h, frame_num, &j);
if(!pic){
if(mmco[i].opcode != MMCO_SHORT2LONG || !h->long_ref[mmco[i].long_arg]
|| h->long_ref[mmco[i].long_arg]->frame_num != frame_num)
av_log(h->s.avctx, AV_LOG_ERROR, "mmco: unref short failure\n");
continue;
}
}
switch(mmco[i].opcode){
case MMCO_SHORT2UNUSED:
if(s->avctx->debug&FF_DEBUG_MMCO)
av_log(h->s.avctx, AV_LOG_DEBUG, "mmco: unref short %d count %d\n", h->mmco[i].short_pic_num, h->short_ref_count);
remove_short(h, frame_num, structure ^ PICT_FRAME);
break;
case MMCO_SHORT2LONG:
if (h->long_ref[mmco[i].long_arg] != pic)
remove_long(h, mmco[i].long_arg, 0);
remove_short_at_index(h, j);
h->long_ref[ mmco[i].long_arg ]= pic;
if (h->long_ref[ mmco[i].long_arg ]){
h->long_ref[ mmco[i].long_arg ]->long_ref=1;
h->long_ref_count++;
}
break;
case MMCO_LONG2UNUSED:
j = pic_num_extract(h, mmco[i].long_arg, &structure);
pic = h->long_ref[j];
if (pic) {
remove_long(h, j, structure ^ PICT_FRAME);
} else if(s->avctx->debug&FF_DEBUG_MMCO)
av_log(h->s.avctx, AV_LOG_DEBUG, "mmco: unref long failure\n");
break;
case MMCO_LONG:
// Comment below left from previous code as it is an interresting note.
/* First field in pair is in short term list or
* at a different long term index.
* This is not allowed; see 7.4.3.3, notes 2 and 3.
* Report the problem and keep the pair where it is,
* and mark this field valid.
*/
if (h->long_ref[mmco[i].long_arg] != s->current_picture_ptr) {
remove_long(h, mmco[i].long_arg, 0);
h->long_ref[ mmco[i].long_arg ]= s->current_picture_ptr;
h->long_ref[ mmco[i].long_arg ]->long_ref=1;
h->long_ref_count++;
}
s->current_picture_ptr->reference |= s->picture_structure;
current_ref_assigned=1;
break;
case MMCO_SET_MAX_LONG:
assert(mmco[i].long_arg <= 16);
// just remove the long term which index is greater than new max
for(j = mmco[i].long_arg; j<16; j++){
remove_long(h, j, 0);
}
break;
case MMCO_RESET:
while(h->short_ref_count){
remove_short(h, h->short_ref[0]->frame_num, 0);
}
for(j = 0; j < 16; j++) {
remove_long(h, j, 0);
}
s->current_picture_ptr->poc=
s->current_picture_ptr->field_poc[0]=
s->current_picture_ptr->field_poc[1]=
h->poc_lsb=
h->poc_msb=
h->frame_num=
s->current_picture_ptr->frame_num= 0;
s->current_picture_ptr->mmco_reset=1;
break;
default: assert(0);
}
}
if (!current_ref_assigned) {
/* Second field of complementary field pair; the first field of
* which is already referenced. If short referenced, it
* should be first entry in short_ref. If not, it must exist
* in long_ref; trying to put it on the short list here is an
* error in the encoded bit stream (ref: 7.4.3.3, NOTE 2 and 3).
*/
if (h->short_ref_count && h->short_ref[0] == s->current_picture_ptr) {
/* Just mark the second field valid */
s->current_picture_ptr->reference = PICT_FRAME;
} else if (s->current_picture_ptr->long_ref) {
av_log(h->s.avctx, AV_LOG_ERROR, "illegal short term reference "
"assignment for second field "
"in complementary field pair "
"(first field is long term)\n");
} else {
pic= remove_short(h, s->current_picture_ptr->frame_num, 0);
if(pic){
av_log(h->s.avctx, AV_LOG_ERROR, "illegal short term buffer state detected\n");
}
if(h->short_ref_count)
memmove(&h->short_ref[1], &h->short_ref[0], h->short_ref_count*sizeof(Picture*));
h->short_ref[0]= s->current_picture_ptr;
h->short_ref_count++;
s->current_picture_ptr->reference |= s->picture_structure;
}
}
if (h->long_ref_count + h->short_ref_count > h->sps.ref_frame_count){
/* We have too many reference frames, probably due to corrupted
* stream. Need to discard one frame. Prevents overrun of the
* short_ref and long_ref buffers.
*/
av_log(h->s.avctx, AV_LOG_ERROR,
"number of reference frames exceeds max (probably "
"corrupt input), discarding one\n");
if (h->long_ref_count && !h->short_ref_count) {
for (i = 0; i < 16; ++i)
if (h->long_ref[i])
break;
assert(i < 16);
remove_long(h, i, 0);
} else {
pic = h->short_ref[h->short_ref_count - 1];
remove_short(h, pic->frame_num, 0);
}
}
print_short_term(h);
print_long_term(h);
return 0;
}
int ff_h264_decode_ref_pic_marking(H264Context *h, GetBitContext *gb){
MpegEncContext * const s = &h->s;
int i;
h->mmco_index= 0;
if(h->nal_unit_type == NAL_IDR_SLICE){ //FIXME fields
s->broken_link= get_bits1(gb) -1;
if(get_bits1(gb)){
h->mmco[0].opcode= MMCO_LONG;
h->mmco[0].long_arg= 0;
h->mmco_index= 1;
}
}else{
if(get_bits1(gb)){ // adaptive_ref_pic_marking_mode_flag
for(i= 0; i<MAX_MMCO_COUNT; i++) {
MMCOOpcode opcode= get_ue_golomb_31(gb);
h->mmco[i].opcode= opcode;
if(opcode==MMCO_SHORT2UNUSED || opcode==MMCO_SHORT2LONG){
h->mmco[i].short_pic_num= (h->curr_pic_num - get_ue_golomb(gb) - 1) & (h->max_pic_num - 1);
/* if(h->mmco[i].short_pic_num >= h->short_ref_count || h->short_ref[ h->mmco[i].short_pic_num ] == NULL){
av_log(s->avctx, AV_LOG_ERROR, "illegal short ref in memory management control operation %d\n", mmco);
return -1;
}*/
}
if(opcode==MMCO_SHORT2LONG || opcode==MMCO_LONG2UNUSED || opcode==MMCO_LONG || opcode==MMCO_SET_MAX_LONG){
unsigned int long_arg= get_ue_golomb_31(gb);
if(long_arg >= 32 || (long_arg >= 16 && !(opcode == MMCO_LONG2UNUSED && FIELD_PICTURE))){
av_log(h->s.avctx, AV_LOG_ERROR, "illegal long ref in memory management control operation %d\n", opcode);
return -1;
}
h->mmco[i].long_arg= long_arg;
}
if(opcode > (unsigned)MMCO_LONG){
av_log(h->s.avctx, AV_LOG_ERROR, "illegal memory management control operation %d\n", opcode);
return -1;
}
if(opcode == MMCO_END)
break;
}
h->mmco_index= i;
}else{
assert(h->long_ref_count + h->short_ref_count <= h->sps.ref_frame_count);
if(h->short_ref_count && h->long_ref_count + h->short_ref_count == h->sps.ref_frame_count &&
!(FIELD_PICTURE && !s->first_field && s->current_picture_ptr->reference)) {
h->mmco[0].opcode= MMCO_SHORT2UNUSED;
h->mmco[0].short_pic_num= h->short_ref[ h->short_ref_count - 1 ]->frame_num;
h->mmco_index= 1;
if (FIELD_PICTURE) {
h->mmco[0].short_pic_num *= 2;
h->mmco[1].opcode= MMCO_SHORT2UNUSED;
h->mmco[1].short_pic_num= h->mmco[0].short_pic_num + 1;
h->mmco_index= 2;
}
}
}
}
return 0;
}