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3176217c60
FFmpeg/libavcodec/h264_parser.c
Anton Khirnov 3176217c60 h264: decouple h264_ps from the h264 decoder 
Make the SPS/PPS parsing independent of the H264Context, to allow
decoupling the parser from the decoder. The change is modelled after the
one done earlier for HEVC.

Move the dequant buffers to the PPS to avoid complex checks whether they
changed and an expensive copy for frame threads.
2016-04-24 10:06:23 +02:00

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/*
* H.26L/H.264/AVC/JVT/14496-10/... parser
* 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 / MPEG4 part10 parser.
* @author Michael Niedermayer <michaelni@gmx.at>
*/
#include <assert.h>
#include <stdint.h>
#include "libavutil/avutil.h"
#include "libavutil/error.h"
#include "libavutil/log.h"
#include "libavutil/mem.h"
#include "libavutil/pixfmt.h"
#include "get_bits.h"
#include "golomb.h"
#include "h264.h"
#include "h264data.h"
#include "internal.h"
#include "mpegutils.h"
#include "parser.h"
typedef struct H264ParseContext {
H264Context h;
ParseContext pc;
H264ParamSets ps;
int got_first;
} H264ParseContext;
static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf,
int buf_size)
{
H264Context *h = &p->h;
int i;
uint32_t state;
ParseContext *pc = &p->pc;
// mb_addr= pc->mb_addr - 1;
state = pc->state;
if (state > 13)
state = 7;
for (i = 0; i < buf_size; i++) {
if (state == 7) {
i += h->h264dsp.startcode_find_candidate(buf + i, buf_size - i);
if (i < buf_size)
state = 2;
} else if (state <= 2) {
if (buf[i] == 1)
state ^= 5; // 2->7, 1->4, 0->5
else if (buf[i])
state = 7;
else
state >>= 1; // 2->1, 1->0, 0->0
} else if (state <= 5) {
int nalu_type = buf[i] & 0x1F;
if (nalu_type == NAL_SEI || nalu_type == NAL_SPS ||
nalu_type == NAL_PPS || nalu_type == NAL_AUD) {
if (pc->frame_start_found) {
i++;
goto found;
}
} else if (nalu_type == NAL_SLICE || nalu_type == NAL_DPA ||
nalu_type == NAL_IDR_SLICE) {
if (pc->frame_start_found) {
state += 8;
continue;
} else
pc->frame_start_found = 1;
}
state = 7;
} else {
// first_mb_in_slice is 0, probably the first nal of a new slice
if (buf[i] & 0x80)
goto found;
state = 7;
}
}
pc->state = state;
return END_NOT_FOUND;
found:
pc->state = 7;
pc->frame_start_found = 0;
return i - (state & 5);
}
static int scan_mmco_reset(AVCodecParserContext *s, GetBitContext *gb)
{
H264PredWeightTable pwt;
int slice_type_nos = s->pict_type & 3;
H264ParseContext *p = s->priv_data;
H264Context *h = &p->h;
int list_count, ref_count[2];
if (p->ps.pps->redundant_pic_cnt_present)
get_ue_golomb(gb); // redundant_pic_count
if (slice_type_nos == AV_PICTURE_TYPE_B)
get_bits1(gb); // direct_spatial_mv_pred
if (ff_h264_parse_ref_count(&list_count, ref_count, gb, p->ps.pps,
slice_type_nos, h->picture_structure) < 0)
return AVERROR_INVALIDDATA;
if (slice_type_nos != AV_PICTURE_TYPE_I) {
int list;
for (list = 0; list < list_count; list++) {
if (get_bits1(gb)) {
int index;
for (index = 0; ; index++) {
unsigned int reordering_of_pic_nums_idc = get_ue_golomb_31(gb);
if (reordering_of_pic_nums_idc < 3)
get_ue_golomb(gb);
else if (reordering_of_pic_nums_idc > 3) {
av_log(h->avctx, AV_LOG_ERROR,
"illegal reordering_of_pic_nums_idc %d\n",
reordering_of_pic_nums_idc);
return AVERROR_INVALIDDATA;
} else
break;
if (index >= ref_count[list]) {
av_log(h->avctx, AV_LOG_ERROR,
"reference count %d overflow\n", index);
return AVERROR_INVALIDDATA;
}
}
}
}
}
if ((p->ps.pps->weighted_pred && slice_type_nos == AV_PICTURE_TYPE_P) ||
(p->ps.pps->weighted_bipred_idc == 1 && slice_type_nos == AV_PICTURE_TYPE_B))
ff_h264_pred_weight_table(gb, p->ps.sps, ref_count, slice_type_nos,
&pwt);
if (get_bits1(gb)) { // adaptive_ref_pic_marking_mode_flag
int i;
for (i = 0; i < MAX_MMCO_COUNT; i++) {
MMCOOpcode opcode = get_ue_golomb_31(gb);
if (opcode > (unsigned) MMCO_LONG) {
av_log(h->avctx, AV_LOG_ERROR,
"illegal memory management control operation %d\n",
opcode);
return AVERROR_INVALIDDATA;
}
if (opcode == MMCO_END)
return 0;
else if (opcode == MMCO_RESET)
return 1;
if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG)
get_ue_golomb(gb);
if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG)
get_ue_golomb_31(gb);
}
}
return 0;
}
/**
* Parse NAL units of found picture and decode some basic information.
*
* @param s parser context.
* @param avctx codec context.
* @param buf buffer with field/frame data.
* @param buf_size size of the buffer.
*/
static inline int parse_nal_units(AVCodecParserContext *s,
AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
H264ParseContext *p = s->priv_data;
H264Context *h = &p->h;
const uint8_t *buf_end = buf + buf_size;
H2645NAL nal = { NULL };
unsigned int pps_id;
unsigned int slice_type;
int state = -1, got_reset = 0;
int field_poc[2];
int ret;
/* set some sane default values */
s->pict_type = AV_PICTURE_TYPE_I;
s->key_frame = 0;
s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
h->avctx = avctx;
ff_h264_reset_sei(h);
if (!buf_size)
return 0;
for (;;) {
const SPS *sps;
int src_length, consumed;
buf = avpriv_find_start_code(buf, buf_end, &state);
if (buf >= buf_end)
break;
--buf;
src_length = buf_end - buf;
switch (state & 0x1f) {
case NAL_SLICE:
case NAL_IDR_SLICE:
// Do not walk the whole buffer just to decode slice header
if ((state & 0x1f) == NAL_IDR_SLICE || ((state >> 5) & 0x3) == 0) {
/* IDR or disposable slice
* No need to decode many bytes because MMCOs shall not be present. */
if (src_length > 60)
src_length = 60;
} else {
/* To decode up to MMCOs */
if (src_length > 1000)
src_length = 1000;
}
break;
}
consumed = ff_h2645_extract_rbsp(buf, src_length, &nal);
if (consumed < 0)
break;
ret = init_get_bits(&nal.gb, nal.data, nal.size * 8);
if (ret < 0)
goto fail;
get_bits1(&nal.gb);
nal.ref_idc = get_bits(&nal.gb, 2);
nal.type = get_bits(&nal.gb, 5);
h->gb = nal.gb;
h->nal_ref_idc = nal.ref_idc;
h->nal_unit_type = nal.type;
switch (h->nal_unit_type) {
case NAL_SPS:
ff_h264_decode_seq_parameter_set(&nal.gb, avctx, &p->ps);
break;
case NAL_PPS:
ff_h264_decode_picture_parameter_set(&nal.gb, avctx, &p->ps,
nal.size_bits);
break;
case NAL_SEI:
ff_h264_decode_sei(h);
break;
case NAL_IDR_SLICE:
s->key_frame = 1;
h->prev_frame_num = 0;
h->prev_frame_num_offset = 0;
h->prev_poc_msb =
h->prev_poc_lsb = 0;
/* fall through */
case NAL_SLICE:
get_ue_golomb(&nal.gb); // skip first_mb_in_slice
slice_type = get_ue_golomb_31(&nal.gb);
s->pict_type = ff_h264_golomb_to_pict_type[slice_type % 5];
if (h->sei_recovery_frame_cnt >= 0) {
/* key frame, since recovery_frame_cnt is set */
s->key_frame = 1;
}
pps_id = get_ue_golomb(&nal.gb);
if (pps_id >= MAX_PPS_COUNT) {
av_log(h->avctx, AV_LOG_ERROR,
"pps_id %u out of range\n", pps_id);
goto fail;
}
if (!p->ps.pps_list[pps_id]) {
av_log(h->avctx, AV_LOG_ERROR,
"non-existing PPS %u referenced\n", pps_id);
goto fail;
}
p->ps.pps = (const PPS*)p->ps.pps_list[pps_id]->data;
if (!p->ps.sps_list[p->ps.pps->sps_id]) {
av_log(h->avctx, AV_LOG_ERROR,
"non-existing SPS %u referenced\n", p->ps.pps->sps_id);
goto fail;
}
p->ps.sps = (SPS*)p->ps.sps_list[p->ps.pps->sps_id]->data;
h->ps.sps = p->ps.sps;
h->ps.pps = p->ps.pps;
sps = p->ps.sps;
h->frame_num = get_bits(&nal.gb, sps->log2_max_frame_num);
s->coded_width = 16 * sps->mb_width;
s->coded_height = 16 * sps->mb_height;
s->width = s->coded_width - (sps->crop_right + sps->crop_left);
s->height = s->coded_height - (sps->crop_top + sps->crop_bottom);
if (s->width <= 0 || s->height <= 0) {
s->width = s->coded_width;
s->height = s->coded_height;
}
switch (sps->bit_depth_luma) {
case 9:
if (CHROMA444(h)) s->format = AV_PIX_FMT_YUV444P9;
else if (CHROMA422(h)) s->format = AV_PIX_FMT_YUV422P9;
else s->format = AV_PIX_FMT_YUV420P9;
break;
case 10:
if (CHROMA444(h)) s->format = AV_PIX_FMT_YUV444P10;
else if (CHROMA422(h)) s->format = AV_PIX_FMT_YUV422P10;
else s->format = AV_PIX_FMT_YUV420P10;
break;
case 8:
if (CHROMA444(h)) s->format = AV_PIX_FMT_YUV444P;
else if (CHROMA422(h)) s->format = AV_PIX_FMT_YUV422P;
else s->format = AV_PIX_FMT_YUV420P;
break;
default:
s->format = AV_PIX_FMT_NONE;
}
avctx->profile = ff_h264_get_profile(sps);
avctx->level = sps->level_idc;
if (sps->frame_mbs_only_flag) {
h->picture_structure = PICT_FRAME;
} else {
if (get_bits1(&nal.gb)) { // field_pic_flag
h->picture_structure = PICT_TOP_FIELD + get_bits1(&nal.gb); // bottom_field_flag
} else {
h->picture_structure = PICT_FRAME;
}
}
if (h->nal_unit_type == NAL_IDR_SLICE)
get_ue_golomb(&nal.gb); /* idr_pic_id */
if (sps->poc_type == 0) {
h->poc_lsb = get_bits(&nal.gb, sps->log2_max_poc_lsb);
if (p->ps.pps->pic_order_present == 1 &&
h->picture_structure == PICT_FRAME)
h->delta_poc_bottom = get_se_golomb(&nal.gb);
}
if (sps->poc_type == 1 &&
!sps->delta_pic_order_always_zero_flag) {
h->delta_poc[0] = get_se_golomb(&nal.gb);
if (p->ps.pps->pic_order_present == 1 &&
h->picture_structure == PICT_FRAME)
h->delta_poc[1] = get_se_golomb(&nal.gb);
}
/* Decode POC of this picture.
* The prev_ values needed for decoding POC of the next picture are not set here. */
field_poc[0] = field_poc[1] = INT_MAX;
ff_init_poc(h, field_poc, &s->output_picture_number);
/* Continue parsing to check if MMCO_RESET is present.
* FIXME: MMCO_RESET could appear in non-first slice.
* Maybe, we should parse all undisposable non-IDR slice of this
* picture until encountering MMCO_RESET in a slice of it. */
if (h->nal_ref_idc && h->nal_unit_type != NAL_IDR_SLICE) {
got_reset = scan_mmco_reset(s, &nal.gb);
if (got_reset < 0)
goto fail;
}
/* Set up the prev_ values for decoding POC of the next picture. */
h->prev_frame_num = got_reset ? 0 : h->frame_num;
h->prev_frame_num_offset = got_reset ? 0 : h->frame_num_offset;
if (h->nal_ref_idc != 0) {
if (!got_reset) {
h->prev_poc_msb = h->poc_msb;
h->prev_poc_lsb = h->poc_lsb;
} else {
h->prev_poc_msb = 0;
h->prev_poc_lsb =
h->picture_structure == PICT_BOTTOM_FIELD ? 0 : field_poc[0];
}
}
if (sps->pic_struct_present_flag) {
switch (h->sei_pic_struct) {
case SEI_PIC_STRUCT_TOP_FIELD:
case SEI_PIC_STRUCT_BOTTOM_FIELD:
s->repeat_pict = 0;
break;
case SEI_PIC_STRUCT_FRAME:
case SEI_PIC_STRUCT_TOP_BOTTOM:
case SEI_PIC_STRUCT_BOTTOM_TOP:
s->repeat_pict = 1;
break;
case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
s->repeat_pict = 2;
break;
case SEI_PIC_STRUCT_FRAME_DOUBLING:
s->repeat_pict = 3;
break;
case SEI_PIC_STRUCT_FRAME_TRIPLING:
s->repeat_pict = 5;
break;
default:
s->repeat_pict = h->picture_structure == PICT_FRAME ? 1 : 0;
break;
}
} else {
s->repeat_pict = h->picture_structure == PICT_FRAME ? 1 : 0;
}
if (h->picture_structure == PICT_FRAME) {
s->picture_structure = AV_PICTURE_STRUCTURE_FRAME;
if (sps->pic_struct_present_flag) {
switch (h->sei_pic_struct) {
case SEI_PIC_STRUCT_TOP_BOTTOM:
case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
s->field_order = AV_FIELD_TT;
break;
case SEI_PIC_STRUCT_BOTTOM_TOP:
case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
s->field_order = AV_FIELD_BB;
break;
default:
s->field_order = AV_FIELD_PROGRESSIVE;
break;
}
} else {
if (field_poc[0] < field_poc[1])
s->field_order = AV_FIELD_TT;
else if (field_poc[0] > field_poc[1])
s->field_order = AV_FIELD_BB;
else
s->field_order = AV_FIELD_PROGRESSIVE;
}
} else {
if (h->picture_structure == PICT_TOP_FIELD)
s->picture_structure = AV_PICTURE_STRUCTURE_TOP_FIELD;
else
s->picture_structure = AV_PICTURE_STRUCTURE_BOTTOM_FIELD;
s->field_order = AV_FIELD_UNKNOWN;
}
av_freep(&nal.rbsp_buffer);
return 0; /* no need to evaluate the rest */
}
buf += consumed;
}
/* didn't find a picture! */
av_log(h->avctx, AV_LOG_ERROR, "missing picture in access unit\n");
fail:
av_freep(&nal.rbsp_buffer);
return -1;
}
static int h264_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
H264ParseContext *p = s->priv_data;
H264Context *h = &p->h;
ParseContext *pc = &p->pc;
int next;
if (!p->got_first) {
p->got_first = 1;
if (avctx->extradata_size) {
h->avctx = avctx;
// must be done like in the decoder.
// otherwise opening the parser, creating extradata,
// and then closing and opening again
// will cause has_b_frames to be always set.
// NB: estimate_timings_from_pts behaves exactly like this.
if (!avctx->has_b_frames)
h->low_delay = 1;
ff_h264_decode_extradata(h);
}
}
if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
next = buf_size;
} else {
next = h264_find_frame_end(p, buf, buf_size);
if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
}
if (next < 0 && next != END_NOT_FOUND) {
assert(pc->last_index + next >= 0);
h264_find_frame_end(p, &pc->buffer[pc->last_index + next], -next); // update state
}
}
parse_nal_units(s, avctx, buf, buf_size);
if (h->sei_cpb_removal_delay >= 0) {
s->dts_sync_point = h->sei_buffering_period_present;
s->dts_ref_dts_delta = h->sei_cpb_removal_delay;
s->pts_dts_delta = h->sei_dpb_output_delay;
} else {
s->dts_sync_point = INT_MIN;
s->dts_ref_dts_delta = INT_MIN;
s->pts_dts_delta = INT_MIN;
}
if (s->flags & PARSER_FLAG_ONCE) {
s->flags &= PARSER_FLAG_COMPLETE_FRAMES;
}
*poutbuf = buf;
*poutbuf_size = buf_size;
return next;
}
static int h264_split(AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
int i;
uint32_t state = -1;
int has_sps = 0;
for (i = 0; i <= buf_size; i++) {
if ((state & 0xFFFFFF1F) == 0x107)
has_sps = 1;
/* if((state&0xFFFFFF1F) == 0x101 ||
* (state&0xFFFFFF1F) == 0x102 ||
* (state&0xFFFFFF1F) == 0x105) {
* }
*/
if ((state & 0xFFFFFF00) == 0x100 && (state & 0xFFFFFF1F) != 0x106 &&
(state & 0xFFFFFF1F) != 0x107 && (state & 0xFFFFFF1F) != 0x108 &&
(state & 0xFFFFFF1F) != 0x109 && (state & 0xFFFFFF1F) != 0x10d &&
(state & 0xFFFFFF1F) != 0x10f) {
if (has_sps) {
while (i > 4 && buf[i - 5] == 0)
i--;
return i - 4;
}
}
if (i < buf_size)
state = (state << 8) | buf[i];
}
return 0;
}
static void h264_close(AVCodecParserContext *s)
{
H264ParseContext *p = s->priv_data;
H264Context *h = &p->h;
ParseContext *pc = &p->pc;
int i;
av_free(pc->buffer);
ff_h264_free_context(h);
for (i = 0; i < FF_ARRAY_ELEMS(p->ps.sps_list); i++)
av_buffer_unref(&p->ps.sps_list[i]);
for (i = 0; i < FF_ARRAY_ELEMS(p->ps.pps_list); i++)
av_buffer_unref(&p->ps.pps_list[i]);
}
static av_cold int init(AVCodecParserContext *s)
{
H264ParseContext *p = s->priv_data;
H264Context *h = &p->h;
h->slice_ctx = av_mallocz(sizeof(*h->slice_ctx));
if (!h->slice_ctx)
return 0;
h->nb_slice_ctx = 1;
h->slice_context_count = 1;
ff_h264dsp_init(&h->h264dsp, 8, 1);
return 0;
}
AVCodecParser ff_h264_parser = {
.codec_ids = { AV_CODEC_ID_H264 },
.priv_data_size = sizeof(H264ParseContext),
.parser_init = init,
.parser_parse = h264_parse,
.parser_close = h264_close,
.split = h264_split,
};
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