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ffmpeg.wasm-core
Commit ed9a20eb authored by Anton Khirnov's avatar Anton Khirnov
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h264: split reading the ref list modifications and actually building the ref list 

This will allow postponing the reference list construction (and by
consequence some other functions, like frame_start) until the whole
slice header has been parsed.
parent fa570590
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Showing with 118 additions and 88 deletions
libavcodec/h264.h
View file @ ed9a20eb
......@@ -391,6 +391,11 @@ typedef struct H264SliceContext {
H264Ref ref_list[2][48]; /**< 0..15: frame refs, 16..47: mbaff field refs.
* Reordered version of default_ref_list
* according to picture reordering in slice header */
struct {
uint8_t op;
uint8_t val;
} ref_modifications[2][32];
int nb_ref_modifications[2];
const uint8_t *intra_pcm_ptr;
int16_t *dc_val_base;
......@@ -657,6 +662,7 @@ int ff_h264_get_slice_type(const H264SliceContext *sl);
int ff_h264_alloc_tables(H264Context *h);
int ff_h264_decode_ref_pic_list_reordering(const H264Context *h, H264SliceContext *sl);
int ff_h264_build_ref_list(const H264Context *h, H264SliceContext *sl);
void ff_h264_remove_all_refs(H264Context *h);
/**
......
libavcodec/h264_refs.c
View file @ ed9a20eb
......@@ -252,7 +252,7 @@ static void h264_fill_mbaff_ref_list(H264SliceContext *sl)
}
}
int ff_h264_decode_ref_pic_list_reordering(const H264Context *h, H264SliceContext *sl)
int ff_h264_build_ref_list(const H264Context *h, H264SliceContext *sl)
{
int list, index, pic_structure;
......@@ -262,102 +262,88 @@ int ff_h264_decode_ref_pic_list_reordering(const H264Context *h, H264SliceContex
h264_initialise_ref_list(h, sl);
for (list = 0; list < sl->list_count; list++) {
if (get_bits1(&sl->gb)) { // ref_pic_list_modification_flag_l[01]
int pred = h->curr_pic_num;
for (index = 0; ; index++) {
unsigned int modification_of_pic_nums_idc = get_ue_golomb_31(&sl->gb);
unsigned int pic_id;
int i;
H264Picture *ref = NULL;
if (modification_of_pic_nums_idc == 3)
break;
if (index >= sl->ref_count[list]) {
av_log(h->avctx, AV_LOG_ERROR, "reference count overflow\n");
return -1;
int pred = h->curr_pic_num;
for (index = 0; index < sl->nb_ref_modifications[list]; index++) {
unsigned int modification_of_pic_nums_idc = sl->ref_modifications[list][index].op;
unsigned int val = sl->ref_modifications[list][index].val;
unsigned int pic_id;
int i;
H264Picture *ref = NULL;
switch (modification_of_pic_nums_idc) {
case 0:
case 1: {
const unsigned int abs_diff_pic_num = val + 1;
int frame_num;
if (abs_diff_pic_num > h->max_pic_num) {
av_log(h->avctx, AV_LOG_ERROR,
"abs_diff_pic_num overflow\n");
return AVERROR_INVALIDDATA;
}
switch (modification_of_pic_nums_idc) {
case 0:
case 1: {
const unsigned int abs_diff_pic_num = get_ue_golomb(&sl->gb) + 1;
int frame_num;
if (abs_diff_pic_num > h->max_pic_num) {
av_log(h->avctx, AV_LOG_ERROR,
"abs_diff_pic_num overflow\n");
return AVERROR_INVALIDDATA;
}
if (modification_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;
break;
if (modification_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;
}
case 2: {
int long_idx;
pic_id = get_ue_golomb(&sl->gb); // long_term_pic_idx
if (i >= 0)
ref->pic_id = pred;
break;
}
case 2: {
int long_idx;
pic_id = val; // long_term_pic_idx
long_idx = pic_num_extract(h, pic_id, &pic_structure);
long_idx = pic_num_extract(h, pic_id, &pic_structure);
if (long_idx > 31) {
av_log(h->avctx, AV_LOG_ERROR,
"long_term_pic_idx overflow\n");
return AVERROR_INVALIDDATA;
}
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;
}
break;
}
default:
if (long_idx > 31) {
av_log(h->avctx, AV_LOG_ERROR,
"illegal modification_of_pic_nums_idc %u\n",
modification_of_pic_nums_idc);
"long_term_pic_idx overflow\n");
return AVERROR_INVALIDDATA;
}
if (i < 0) {
av_log(h->avctx, AV_LOG_ERROR,
"reference picture missing during reorder\n");
memset(&sl->ref_list[list][index], 0, sizeof(sl->ref_list[0][0])); // FIXME
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 {
for (i = index; i + 1 < sl->ref_count[list]; i++) {
if (sl->ref_list[list][i].parent &&
ref->long_ref == sl->ref_list[list][i].parent->long_ref &&
ref->pic_id == sl->ref_list[list][i].pic_id)
break;
}
for (; i > index; i--) {
sl->ref_list[list][i] = sl->ref_list[list][i - 1];
}
ref_from_h264pic(&sl->ref_list[list][index], ref);
if (FIELD_PICTURE(h)) {
pic_as_field(&sl->ref_list[list][index], pic_structure);
}
i = -1;
}
break;
}
}
if (i < 0) {
av_log(h->avctx, AV_LOG_ERROR,
"reference picture missing during reorder\n");
memset(&sl->ref_list[list][index], 0, sizeof(sl->ref_list[0][0])); // FIXME
} else {
for (i = index; i + 1 < sl->ref_count[list]; i++) {
if (sl->ref_list[list][i].parent &&
ref->long_ref == sl->ref_list[list][i].parent->long_ref &&
ref->pic_id == sl->ref_list[list][i].pic_id)
break;
}
for (; i > index; i--) {
sl->ref_list[list][i] = sl->ref_list[list][i - 1];
}
ref_from_h264pic(&sl->ref_list[list][index], ref);
if (FIELD_PICTURE(h)) {
pic_as_field(&sl->ref_list[list][index], pic_structure);
}
}
}
......@@ -380,6 +366,41 @@ int ff_h264_decode_ref_pic_list_reordering(const H264Context *h, H264SliceContex
return 0;
}
int ff_h264_decode_ref_pic_list_reordering(const H264Context *h, H264SliceContext *sl)
{
int list, index;
sl->nb_ref_modifications[0] = 0;
sl->nb_ref_modifications[1] = 0;
for (list = 0; list < sl->list_count; list++) {
if (!get_bits1(&sl->gb)) // ref_pic_list_modification_flag_l[01]
continue;
for (index = 0; ; index++) {
unsigned int op = get_ue_golomb_31(&sl->gb);
if (op == 3)
break;
if (index >= sl->ref_count[list]) {
av_log(h->avctx, AV_LOG_ERROR, "reference count overflow\n");
return AVERROR_INVALIDDATA;
} else if (op > 2) {
av_log(h->avctx, AV_LOG_ERROR,
"illegal modification_of_pic_nums_idc %u\n",
op);
return AVERROR_INVALIDDATA;
}
sl->ref_modifications[list][index].val = get_ue_golomb(&sl->gb);
sl->ref_modifications[list][index].op = op;
sl->nb_ref_modifications[list]++;
}
}
return 0;
}
/**
* Mark a picture as no longer needed for reference. The refmask
* argument allows unreferencing of individual fields or the whole frame.
......
libavcodec/h264_slice.c
View file @ ed9a20eb
......@@ -1347,6 +1347,9 @@ static int h264_slice_header_parse(H264Context *h, H264SliceContext *sl)
sl->ref_count[1] = sl->ref_count[0] = 0;
return ret;
}
ret = ff_h264_build_ref_list(h, sl);
if (ret < 0)
return ret;
}
if ((pps->weighted_pred && sl->slice_type_nos == AV_PICTURE_TYPE_P) ||
......
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