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FFmpeg/libavcodec/h264dec.c

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/*
* H.26L/H.264/AVC/JVT/14496-10/... decoder
* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
*
* 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
* H.264 / AVC / MPEG-4 part10 codec.
* @author Michael Niedermayer <michaelni@gmx.at>
*/
#include "libavutil/display.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libavutil/stereo3d.h"
#include "libavutil/timer.h"
#include "internal.h"
#include "bytestream.h"
#include "cabac.h"
#include "cabac_functions.h"
#include "error_resilience.h"
#include "avcodec.h"
#include "h264.h"
#include "h264dec.h"
#include "h2645_parse.h"
#include "h264data.h"
#include "h264chroma.h"
#include "h264_mvpred.h"
#include "h264_ps.h"
#include "golomb.h"
#include "mathops.h"
#include "me_cmp.h"
#include "mpegutils.h"
#include "profiles.h"
#include "rectangle.h"
#include "thread.h"
#include <assert.h>
const uint16_t ff_h264_mb_sizes[4] = { 256, 384, 512, 768 };
static void h264_er_decode_mb(void *opaque, int ref, int mv_dir, int mv_type,
int (*mv)[2][4][2],
int mb_x, int mb_y, int mb_intra, int mb_skipped)
{
H264Context *h = opaque;
H264SliceContext *sl = &h->slice_ctx[0];
sl->mb_x = mb_x;
sl->mb_y = mb_y;
sl->mb_xy = mb_x + mb_y * h->mb_stride;
memset(sl->non_zero_count_cache, 0, sizeof(sl->non_zero_count_cache));
assert(ref >= 0);
/* FIXME: It is possible albeit uncommon that slice references
* differ between slices. We take the easy approach and ignore
* it for now. If this turns out to have any relevance in
* practice then correct remapping should be added. */
if (ref >= sl->ref_count[0])
ref = 0;
fill_rectangle(&h->cur_pic.ref_index[0][4 * sl->mb_xy],
2, 2, 2, ref, 1);
fill_rectangle(&sl->ref_cache[0][scan8[0]], 4, 4, 8, ref, 1);
fill_rectangle(sl->mv_cache[0][scan8[0]], 4, 4, 8,
pack16to32((*mv)[0][0][0], (*mv)[0][0][1]), 4);
assert(!FRAME_MBAFF(h));
ff_h264_hl_decode_mb(h, &h->slice_ctx[0]);
}
void ff_h264_draw_horiz_band(const H264Context *h, H264SliceContext *sl,
int y, int height)
{
AVCodecContext *avctx = h->avctx;
const AVFrame *src = h->cur_pic.f;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(avctx->pix_fmt);
int vshift = desc->log2_chroma_h;
const int field_pic = h->picture_structure != PICT_FRAME;
if (field_pic) {
height <<= 1;
y <<= 1;
}
height = FFMIN(height, avctx->height - y);
if (field_pic && h->first_field && !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD))
return;
if (avctx->draw_horiz_band) {
int offset[AV_NUM_DATA_POINTERS];
int i;
offset[0] = y * src->linesize[0];
offset[1] =
offset[2] = (y >> vshift) * src->linesize[1];
for (i = 3; i < AV_NUM_DATA_POINTERS; i++)
offset[i] = 0;
emms_c();
avctx->draw_horiz_band(avctx, src, offset,
y, h->picture_structure, height);
}
}
void ff_h264_free_tables(H264Context *h)
{
int i;
av_freep(&h->intra4x4_pred_mode);
av_freep(&h->chroma_pred_mode_table);
av_freep(&h->cbp_table);
av_freep(&h->mvd_table[0]);
av_freep(&h->mvd_table[1]);
av_freep(&h->direct_table);
av_freep(&h->non_zero_count);
av_freep(&h->slice_table_base);
h->slice_table = NULL;
av_freep(&h->list_counts);
av_freep(&h->mb2b_xy);
av_freep(&h->mb2br_xy);
av_buffer_pool_uninit(&h->qscale_table_pool);
av_buffer_pool_uninit(&h->mb_type_pool);
av_buffer_pool_uninit(&h->motion_val_pool);
av_buffer_pool_uninit(&h->ref_index_pool);
for (i = 0; i < h->nb_slice_ctx; i++) {
H264SliceContext *sl = &h->slice_ctx[i];
av_freep(&sl->dc_val_base);
av_freep(&sl->er.mb_index2xy);
av_freep(&sl->er.error_status_table);
av_freep(&sl->er.er_temp_buffer);
av_freep(&sl->bipred_scratchpad);
av_freep(&sl->edge_emu_buffer);
av_freep(&sl->top_borders[0]);
av_freep(&sl->top_borders[1]);
sl->bipred_scratchpad_allocated = 0;
sl->edge_emu_buffer_allocated = 0;
sl->top_borders_allocated[0] = 0;
sl->top_borders_allocated[1] = 0;
}
}
int ff_h264_alloc_tables(H264Context *h)
{
const int big_mb_num = h->mb_stride * (h->mb_height + 1);
const int row_mb_num = h->mb_stride * 2 * h->nb_slice_ctx;
int x, y;
FF_ALLOCZ_OR_GOTO(h->avctx, h->intra4x4_pred_mode,
row_mb_num * 8 * sizeof(uint8_t), fail)
h->slice_ctx[0].intra4x4_pred_mode = h->intra4x4_pred_mode;
FF_ALLOCZ_OR_GOTO(h->avctx, h->non_zero_count,
big_mb_num * 48 * sizeof(uint8_t), fail)
FF_ALLOCZ_OR_GOTO(h->avctx, h->slice_table_base,
(big_mb_num + h->mb_stride) * sizeof(*h->slice_table_base), fail)
FF_ALLOCZ_OR_GOTO(h->avctx, h->cbp_table,
big_mb_num * sizeof(uint16_t), fail)
FF_ALLOCZ_OR_GOTO(h->avctx, h->chroma_pred_mode_table,
big_mb_num * sizeof(uint8_t), fail)
FF_ALLOCZ_OR_GOTO(h->avctx, h->mvd_table[0],
16 * row_mb_num * sizeof(uint8_t), fail);
FF_ALLOCZ_OR_GOTO(h->avctx, h->mvd_table[1],
16 * row_mb_num * sizeof(uint8_t), fail);
h->slice_ctx[0].mvd_table[0] = h->mvd_table[0];
h->slice_ctx[0].mvd_table[1] = h->mvd_table[1];
FF_ALLOCZ_OR_GOTO(h->avctx, h->direct_table,
4 * big_mb_num * sizeof(uint8_t), fail);
FF_ALLOCZ_OR_GOTO(h->avctx, h->list_counts,
big_mb_num * sizeof(uint8_t), fail)
memset(h->slice_table_base, -1,
(big_mb_num + h->mb_stride) * sizeof(*h->slice_table_base));
h->slice_table = h->slice_table_base + h->mb_stride * 2 + 1;
FF_ALLOCZ_OR_GOTO(h->avctx, h->mb2b_xy,
big_mb_num * sizeof(uint32_t), fail);
FF_ALLOCZ_OR_GOTO(h->avctx, h->mb2br_xy,
big_mb_num * sizeof(uint32_t), fail);
for (y = 0; y < h->mb_height; y++)
for (x = 0; x < h->mb_width; x++) {
const int mb_xy = x + y * h->mb_stride;
const int b_xy = 4 * x + 4 * y * h->b_stride;
h->mb2b_xy[mb_xy] = b_xy;
h->mb2br_xy[mb_xy] = 8 * (FMO ? mb_xy : (mb_xy % (2 * h->mb_stride)));
}
return 0;
fail:
ff_h264_free_tables(h);
return AVERROR(ENOMEM);
}
/**
* Init context
* Allocate buffers which are not shared amongst multiple threads.
*/
int ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl)
{
ERContext *er = &sl->er;
int mb_array_size = h->mb_height * h->mb_stride;
int y_size = (2 * h->mb_width + 1) * (2 * h->mb_height + 1);
int c_size = h->mb_stride * (h->mb_height + 1);
int yc_size = y_size + 2 * c_size;
int x, y, i;
sl->ref_cache[0][scan8[5] + 1] =
sl->ref_cache[0][scan8[7] + 1] =
sl->ref_cache[0][scan8[13] + 1] =
sl->ref_cache[1][scan8[5] + 1] =
sl->ref_cache[1][scan8[7] + 1] =
sl->ref_cache[1][scan8[13] + 1] = PART_NOT_AVAILABLE;
if (CONFIG_ERROR_RESILIENCE) {
/* init ER */
er->avctx = h->avctx;
er->decode_mb = h264_er_decode_mb;
er->opaque = h;
er->quarter_sample = 1;
er->mb_num = h->mb_num;
er->mb_width = h->mb_width;
er->mb_height = h->mb_height;
er->mb_stride = h->mb_stride;
er->b8_stride = h->mb_width * 2 + 1;
// error resilience code looks cleaner with this
FF_ALLOCZ_OR_GOTO(h->avctx, er->mb_index2xy,
(h->mb_num + 1) * sizeof(int), fail);
for (y = 0; y < h->mb_height; y++)
for (x = 0; x < h->mb_width; x++)
er->mb_index2xy[x + y * h->mb_width] = x + y * h->mb_stride;
er->mb_index2xy[h->mb_height * h->mb_width] = (h->mb_height - 1) *
h->mb_stride + h->mb_width;
FF_ALLOCZ_OR_GOTO(h->avctx, er->error_status_table,
mb_array_size * sizeof(uint8_t), fail);
FF_ALLOC_OR_GOTO(h->avctx, er->er_temp_buffer,
h->mb_height * h->mb_stride, fail);
FF_ALLOCZ_OR_GOTO(h->avctx, sl->dc_val_base,
yc_size * sizeof(int16_t), fail);
er->dc_val[0] = sl->dc_val_base + h->mb_width * 2 + 2;
er->dc_val[1] = sl->dc_val_base + y_size + h->mb_stride + 1;
er->dc_val[2] = er->dc_val[1] + c_size;
for (i = 0; i < yc_size; i++)
sl->dc_val_base[i] = 1024;
}
return 0;
fail:
return AVERROR(ENOMEM); // ff_h264_free_tables will clean up for us
}
static int h264_init_context(AVCodecContext *avctx, H264Context *h)
{
int i;
h->avctx = avctx;
h->picture_structure = PICT_FRAME;
h->workaround_bugs = avctx->workaround_bugs;
h->flags = avctx->flags;
h->poc.prev_poc_msb = 1 << 16;
h->recovery_frame = -1;
h->frame_recovered = 0;
h->next_outputed_poc = INT_MIN;
for (i = 0; i < MAX_DELAYED_PIC_COUNT; i++)
h->last_pocs[i] = INT_MIN;
ff_h264_sei_uninit(&h->sei);
avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
h->nb_slice_ctx = (avctx->active_thread_type & FF_THREAD_SLICE) ? avctx->thread_count : 1;
h->slice_ctx = av_mallocz_array(h->nb_slice_ctx, sizeof(*h->slice_ctx));
if (!h->slice_ctx) {
h->nb_slice_ctx = 0;
return AVERROR(ENOMEM);
}
for (i = 0; i < H264_MAX_PICTURE_COUNT; i++) {
h->DPB[i].f = av_frame_alloc();
if (!h->DPB[i].f)
return AVERROR(ENOMEM);
}
h->cur_pic.f = av_frame_alloc();
if (!h->cur_pic.f)
return AVERROR(ENOMEM);
h->output_frame = av_frame_alloc();
if (!h->output_frame)
return AVERROR(ENOMEM);
for (i = 0; i < h->nb_slice_ctx; i++)
h->slice_ctx[i].h264 = h;
return 0;
}
static av_cold int h264_decode_end(AVCodecContext *avctx)
{
H264Context *h = avctx->priv_data;
int i;
ff_h264_free_tables(h);
for (i = 0; i < H264_MAX_PICTURE_COUNT; i++) {
ff_h264_unref_picture(h, &h->DPB[i]);
av_frame_free(&h->DPB[i].f);
}
h->cur_pic_ptr = NULL;
av_freep(&h->slice_ctx);
h->nb_slice_ctx = 0;
for (i = 0; i < MAX_SPS_COUNT; i++)
av_buffer_unref(&h->ps.sps_list[i]);
for (i = 0; i < MAX_PPS_COUNT; i++)
av_buffer_unref(&h->ps.pps_list[i]);
ff_h2645_packet_uninit(&h->pkt);
ff_h264_unref_picture(h, &h->cur_pic);
av_frame_free(&h->cur_pic.f);
av_frame_free(&h->output_frame);
return 0;
}
static AVOnce h264_vlc_init = AV_ONCE_INIT;
av_cold int ff_h264_decode_init(AVCodecContext *avctx)
{
H264Context *h = avctx->priv_data;
int ret;
ret = h264_init_context(avctx, h);
if (ret < 0)
return ret;
ret = ff_thread_once(&h264_vlc_init, ff_h264_decode_init_vlc);
if (ret != 0) {
av_log(avctx, AV_LOG_ERROR, "pthread_once has failed.");
return AVERROR_UNKNOWN;
}
if (avctx->ticks_per_frame == 1)
h->avctx->framerate.num *= 2;
avctx->ticks_per_frame = 2;
if (avctx->extradata_size > 0 && avctx->extradata) {
ret = ff_h264_decode_extradata(avctx->extradata, avctx->extradata_size,
&h->ps, &h->is_avc, &h->nal_length_size,
avctx->err_recognition, avctx);
if (ret < 0) {
h264_decode_end(avctx);
return ret;
}
}
if (h->ps.sps && h->ps.sps->bitstream_restriction_flag &&
h->avctx->has_b_frames < h->ps.sps->num_reorder_frames) {
h->avctx->has_b_frames = h->ps.sps->num_reorder_frames;
}
avctx->internal->allocate_progress = 1;
if (h->enable_er) {
av_log(avctx, AV_LOG_WARNING,
"Error resilience is enabled. It is unsafe and unsupported and may crash. "
"Use it at your own risk\n");
}
return 0;
}
static int decode_init_thread_copy(AVCodecContext *avctx)
{
H264Context *h = avctx->priv_data;
int ret;
if (!avctx->internal->is_copy)
return 0;
memset(h, 0, sizeof(*h));
ret = h264_init_context(avctx, h);
if (ret < 0)
return ret;
h->context_initialized = 0;
return 0;
}
/**
* instantaneous decoder refresh.
*/
static void idr(H264Context *h)
{
ff_h264_remove_all_refs(h);
h->poc.prev_frame_num =
h->poc.prev_frame_num_offset =
h->poc.prev_poc_msb =
h->poc.prev_poc_lsb = 0;
}
/* forget old pics after a seek */
void ff_h264_flush_change(H264Context *h)
{
int i;
for (i = 0; i < MAX_DELAYED_PIC_COUNT; i++)
h->last_pocs[i] = INT_MIN;
h->next_outputed_poc = INT_MIN;
h->prev_interlaced_frame = 1;
idr(h);
if (h->cur_pic_ptr)
h->cur_pic_ptr->reference = 0;
h->first_field = 0;
ff_h264_sei_uninit(&h->sei);
h->recovery_frame = -1;
h->frame_recovered = 0;
}
/* forget old pics after a seek */
static void flush_dpb(AVCodecContext *avctx)
{
H264Context *h = avctx->priv_data;
int i;
memset(h->delayed_pic, 0, sizeof(h->delayed_pic));
ff_h264_flush_change(h);
for (i = 0; i < H264_MAX_PICTURE_COUNT; i++)
ff_h264_unref_picture(h, &h->DPB[i]);
h->cur_pic_ptr = NULL;
ff_h264_unref_picture(h, &h->cur_pic);
h->mb_y = 0;
ff_h264_free_tables(h);
h->context_initialized = 0;
}
static int get_last_needed_nal(H264Context *h)
{
int nals_needed = 0;
int i, ret;
for (i = 0; i < h->pkt.nb_nals; i++) {
H2645NAL *nal = &h->pkt.nals[i];
GetBitContext gb;
/* packets can sometimes contain multiple PPS/SPS,
* e.g. two PAFF field pictures in one packet, or a demuxer
* which splits NALs strangely if so, when frame threading we
* can't start the next thread until we've read all of them */
switch (nal->type) {
case H264_NAL_SPS:
case H264_NAL_PPS:
nals_needed = i;
break;
case H264_NAL_DPA:
case H264_NAL_IDR_SLICE:
case H264_NAL_SLICE:
ret = init_get_bits8(&gb, nal->data + 1, nal->size - 1);
if (ret < 0) {
av_log(h->avctx, AV_LOG_ERROR, "Invalid zero-sized VCL NAL unit\n");
if (h->avctx->err_recognition & AV_EF_EXPLODE)
return ret;
break;
}
if (!get_ue_golomb(&gb))
nals_needed = i;
}
}
return nals_needed;
}
static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size)
{
AVCodecContext *const avctx = h->avctx;
int nals_needed = 0; ///< number of NALs that need decoding before the next frame thread starts
int i, ret = 0;
if (!(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS)) {
h->current_slice = 0;
if (!h->first_field)
h->cur_pic_ptr = NULL;
ff_h264_sei_uninit(&h->sei);
}
ret = ff_h2645_packet_split(&h->pkt, buf, buf_size, avctx, h->is_avc,
h->nal_length_size, avctx->codec_id);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR,
"Error splitting the input into NAL units.\n");
/* There are samples in the wild with mp4-style extradata, but Annex B
* data in the packets. If we fail parsing the packet as mp4, try it again
* as Annex B. */
if (h->is_avc && !(avctx->err_recognition & AV_EF_EXPLODE)) {
int err = ff_h2645_packet_split(&h->pkt, buf, buf_size, avctx, 0, 0,
avctx->codec_id);
if (err >= 0) {
av_log(avctx, AV_LOG_WARNING,
"The stream seems to contain AVCC extradata with Annex B "
"formatted data, which is invalid.");
h->is_avc = 0;
ret = 0;
}
}
if (ret < 0)
return ret;
}
if (avctx->active_thread_type & FF_THREAD_FRAME)
nals_needed = get_last_needed_nal(h);
for (i = 0; i < h->pkt.nb_nals; i++) {
H2645NAL *nal = &h->pkt.nals[i];
int max_slice_ctx, err;
if (avctx->skip_frame >= AVDISCARD_NONREF &&
nal->ref_idc == 0 && nal->type != H264_NAL_SEI)
continue;
// FIXME these should stop being context-global variables
h->nal_ref_idc = nal->ref_idc;
h->nal_unit_type = nal->type;
err = 0;
switch (nal->type) {
case H264_NAL_IDR_SLICE:
idr(h); // FIXME ensure we don't lose some frames if there is reordering
case H264_NAL_SLICE:
if ((err = ff_h264_queue_decode_slice(h, nal)))
break;
if (avctx->active_thread_type & FF_THREAD_FRAME && !h->avctx->hwaccel &&
i >= nals_needed && !h->setup_finished && h->cur_pic_ptr) {
ff_thread_finish_setup(avctx);
h->setup_finished = 1;
}
max_slice_ctx = avctx->hwaccel ? 1 : h->nb_slice_ctx;
if (h->nb_slice_ctx_queued == max_slice_ctx) {
if (avctx->hwaccel) {
ret = avctx->hwaccel->decode_slice(avctx, nal->raw_data, nal->raw_size);
h->nb_slice_ctx_queued = 0;
} else
ret = ff_h264_execute_decode_slices(h);
if (ret < 0 && (h->avctx->err_recognition & AV_EF_EXPLODE))
goto end;
}
break;
case H264_NAL_DPA:
case H264_NAL_DPB:
case H264_NAL_DPC:
avpriv_request_sample(avctx, "data partitioning");
ret = AVERROR(ENOSYS);
goto end;
break;
case H264_NAL_SEI:
ret = ff_h264_sei_decode(&h->sei, &nal->gb, &h->ps, avctx);
if (ret < 0 && (h->avctx->err_recognition & AV_EF_EXPLODE))
goto end;
break;
case H264_NAL_SPS:
ret = ff_h264_decode_seq_parameter_set(&nal->gb, avctx, &h->ps);
if (ret < 0 && (h->avctx->err_recognition & AV_EF_EXPLODE))
goto end;
break;
case H264_NAL_PPS:
ret = ff_h264_decode_picture_parameter_set(&nal->gb, avctx, &h->ps,
nal->size_bits);
if (ret < 0 && (h->avctx->err_recognition & AV_EF_EXPLODE))
goto end;
break;
case H264_NAL_AUD:
case H264_NAL_END_SEQUENCE:
case H264_NAL_END_STREAM:
case H264_NAL_FILLER_DATA:
case H264_NAL_SPS_EXT:
case H264_NAL_AUXILIARY_SLICE:
break;
default:
av_log(avctx, AV_LOG_DEBUG, "Unknown NAL code: %d (%d bits)\n",
nal->type, nal->size_bits);
}
if (err < 0) {
av_log(h->avctx, AV_LOG_ERROR, "decode_slice_header error\n");
}
}
ret = ff_h264_execute_decode_slices(h);
if (ret < 0 && (h->avctx->err_recognition & AV_EF_EXPLODE))
goto end;
ret = 0;
end:
/* clean up */
if (h->cur_pic_ptr && !h->droppable) {
ff_thread_report_progress(&h->cur_pic_ptr->tf, INT_MAX,
h->picture_structure == PICT_BOTTOM_FIELD);
}
return (ret < 0) ? ret : buf_size;
}
/**
* Return the number of bytes consumed for building the current frame.
*/
static int get_consumed_bytes(int pos, int buf_size)
{
if (pos == 0)
pos = 1; // avoid infinite loops (I doubt that is needed but...)
if (pos + 10 > buf_size)
pos = buf_size; // oops ;)
return pos;
}
static int output_frame(H264Context *h, AVFrame *dst, AVFrame *src)
{
int i;
int ret = av_frame_ref(dst, src);
if (ret < 0)
return ret;
if (!h->ps.sps || !h->ps.sps->crop)
return 0;
for (i = 0; i < 3; i++) {
int hshift = (i > 0) ? h->chroma_x_shift : 0;
int vshift = (i > 0) ? h->chroma_y_shift : 0;
int off = ((h->ps.sps->crop_left >> hshift) << h->pixel_shift) +
(h->ps.sps->crop_top >> vshift) * dst->linesize[i];
dst->data[i] += off;
}
return 0;
}
static int h264_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
H264Context *h = avctx->priv_data;
AVFrame *pict = data;
int buf_index = 0;
int ret;
const uint8_t *new_extradata;
int new_extradata_size;
h->flags = avctx->flags;
h->setup_finished = 0;
h->nb_slice_ctx_queued = 0;
/* end of stream, output what is still in the buffers */
out:
if (buf_size == 0) {
H264Picture *out;
int i, out_idx;
h->cur_pic_ptr = NULL;
// FIXME factorize this with the output code below
out = h->delayed_pic[0];
out_idx = 0;
for (i = 1;
h->delayed_pic[i] &&
!h->delayed_pic[i]->f->key_frame &&
!h->delayed_pic[i]->mmco_reset;
i++)
if (h->delayed_pic[i]->poc < out->poc) {
out = h->delayed_pic[i];
out_idx = i;
}
for (i = out_idx; h->delayed_pic[i]; i++)
h->delayed_pic[i] = h->delayed_pic[i + 1];
if (out) {
ret = output_frame(h, pict, out->f);
if (ret < 0)
return ret;
*got_frame = 1;
}
return buf_index;
}
new_extradata_size = 0;
new_extradata = av_packet_get_side_data(avpkt, AV_PKT_DATA_NEW_EXTRADATA,
&new_extradata_size);
if (new_extradata_size > 0 && new_extradata) {
ret = ff_h264_decode_extradata(new_extradata, new_extradata_size,
&h->ps, &h->is_avc, &h->nal_length_size,
avctx->err_recognition, avctx);
if (ret < 0)
return ret;
}
buf_index = decode_nal_units(h, buf, buf_size);
if (buf_index < 0)
return AVERROR_INVALIDDATA;
if (!h->cur_pic_ptr && h->nal_unit_type == H264_NAL_END_SEQUENCE) {
buf_size = 0;
goto out;
}
if (!(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS) && !h->cur_pic_ptr) {
if (avctx->skip_frame >= AVDISCARD_NONREF)
return 0;
av_log(avctx, AV_LOG_ERROR, "no frame!\n");
return AVERROR_INVALIDDATA;
}
if (!(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS) ||
(h->mb_y >= h->mb_height && h->mb_height)) {
ff_h264_field_end(h, &h->slice_ctx[0], 0);
*got_frame = 0;
if (h->output_frame->buf[0]) {
ret = output_frame(h, pict, h->output_frame) ;
av_frame_unref(h->output_frame);
if (ret < 0)
return ret;
*got_frame = 1;
}
}
assert(pict->buf[0] || !*got_frame);
return get_consumed_bytes(buf_index, buf_size);
}
#define OFFSET(x) offsetof(H264Context, x)
#define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
static const AVOption h264_options[] = {
{ "enable_er", "Enable error resilience on damaged frames (unsafe)", OFFSET(enable_er), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VD },
{ NULL },
};
static const AVClass h264_class = {
.class_name = "h264",
.item_name = av_default_item_name,
.option = h264_options,
.version = LIBAVUTIL_VERSION_INT,
};
AVCodec ff_h264_decoder = {
.name = "h264",
.long_name = NULL_IF_CONFIG_SMALL("H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_H264,
.priv_data_size = sizeof(H264Context),
.init = ff_h264_decode_init,
.close = h264_decode_end,
.decode = h264_decode_frame,
.capabilities = /*AV_CODEC_CAP_DRAW_HORIZ_BAND |*/ AV_CODEC_CAP_DR1 |
AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS |
AV_CODEC_CAP_FRAME_THREADS,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
.flush = flush_dpb,
.init_thread_copy = ONLY_IF_THREADS_ENABLED(decode_init_thread_copy),
.update_thread_context = ONLY_IF_THREADS_ENABLED(ff_h264_update_thread_context),
.profiles = NULL_IF_CONFIG_SMALL(ff_h264_profiles),
.priv_class = &h264_class,
};