FFmpeg
h264_redundant_pps_bsf.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include <string.h>
20 
21 #include "libavutil/common.h"
22 #include "libavutil/mem.h"
23 
24 #include "bsf.h"
25 #include "cbs.h"
26 #include "cbs_h264.h"
27 #include "h264.h"
28 
29 
30 typedef struct H264RedundantPPSContext {
33 
35 
40 
41 
43  H264RawPPS *pps)
44 {
45  // Record the current value of pic_init_qp in order to fix up
46  // following slices, then overwrite with the global value.
48  pps->pic_init_qp_minus26 = ctx->global_pic_init_qp - 26;
49 
50  // Some PPSs have this set, so it must be set in all of them.
51  // (Slices which do not use such a PPS on input will still have
52  // *_weight_l*flag as zero and therefore write equivalently.)
53  pps->weighted_pred_flag = 1;
54 
55  return 0;
56 }
57 
59  H264RawSliceHeader *slice)
60 {
61  int qp;
62 
63  qp = ctx->current_pic_init_qp + slice->slice_qp_delta;
64  slice->slice_qp_delta = qp - ctx->global_pic_init_qp;
65 
66  return 0;
67 }
68 
70 {
73  int au_has_sps;
74  int err, i;
75 
76  err = ff_bsf_get_packet_ref(bsf, pkt);
77  if (err < 0)
78  return err;
79 
80  err = ff_cbs_read_packet(ctx->input, au, pkt);
81  if (err < 0)
82  goto fail;
83 
84  au_has_sps = 0;
85  for (i = 0; i < au->nb_units; i++) {
86  CodedBitstreamUnit *nal = &au->units[i];
87 
88  if (nal->type == H264_NAL_SPS)
89  au_has_sps = 1;
90  if (nal->type == H264_NAL_PPS) {
91  err = h264_redundant_pps_fixup_pps(ctx, nal->content);
92  if (err < 0)
93  goto fail;
94  if (!au_has_sps) {
95  av_log(bsf, AV_LOG_VERBOSE, "Deleting redundant PPS "
96  "at %"PRId64".\n", pkt->pts);
97  ff_cbs_delete_unit(ctx->input, au, i);
98  i--;
99  continue;
100  }
101  }
102  if (nal->type == H264_NAL_SLICE ||
103  nal->type == H264_NAL_IDR_SLICE) {
104  H264RawSlice *slice = nal->content;
106  }
107  }
108 
109  err = ff_cbs_write_packet(ctx->output, pkt, au);
110  if (err < 0)
111  goto fail;
112 
113  err = 0;
114 fail:
115  ff_cbs_fragment_reset(ctx->output, au);
116  if (err < 0)
117  av_packet_unref(pkt);
118 
119  return err;
120 }
121 
123 {
126  int err, i;
127 
128  err = ff_cbs_init(&ctx->input, AV_CODEC_ID_H264, bsf);
129  if (err < 0)
130  return err;
131 
132  err = ff_cbs_init(&ctx->output, AV_CODEC_ID_H264, bsf);
133  if (err < 0)
134  return err;
135 
136  ctx->global_pic_init_qp = 26;
137 
138  if (bsf->par_in->extradata) {
139  err = ff_cbs_read_extradata(ctx->input, au, bsf->par_in);
140  if (err < 0) {
141  av_log(bsf, AV_LOG_ERROR, "Failed to read extradata.\n");
142  goto fail;
143  }
144 
145  for (i = 0; i < au->nb_units; i++) {
146  if (au->units[i].type == H264_NAL_PPS) {
147  err = h264_redundant_pps_fixup_pps(ctx, au->units[i].content);
148  if (err < 0)
149  goto fail;
150  }
151  }
152 
154  err = ff_cbs_write_extradata(ctx->output, bsf->par_out, au);
155  if (err < 0) {
156  av_log(bsf, AV_LOG_ERROR, "Failed to write extradata.\n");
157  goto fail;
158  }
159  }
160 
161  err = 0;
162 fail:
163  ff_cbs_fragment_reset(ctx->output, au);
164  return err;
165 }
166 
168 {
171 }
172 
174 {
176 
178  ff_cbs_close(&ctx->input);
179  ff_cbs_close(&ctx->output);
180 }
181 
184 };
185 
187  .name = "h264_redundant_pps",
188  .priv_data_size = sizeof(H264RedundantPPSContext),
191  .close = &h264_redundant_pps_close,
194 };
static int h264_redundant_pps_init(AVBSFContext *bsf)
int nb_units
Number of units in this fragment.
Definition: cbs.h:147
AVCodecParameters * par_out
Parameters of the output stream.
Definition: avcodec.h:5808
static void flush(AVCodecContext *avctx)
Memory handling functions.
int ff_cbs_write_packet(CodedBitstreamContext *ctx, AVPacket *pkt, CodedBitstreamFragment *frag)
Write the bitstream of a fragment to a packet.
Definition: cbs.c:345
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int ff_cbs_init(CodedBitstreamContext **ctx_ptr, enum AVCodecID codec_id, void *log_ctx)
Create and initialise a new context for the given codec.
Definition: cbs.c:74
void ff_cbs_delete_unit(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, int position)
Delete a unit from a fragment and free all memory it uses.
Definition: cbs.c:740
CodedBitstreamUnitType type
Codec-specific type of this unit.
Definition: cbs.h:68
The bitstream filter state.
Definition: avcodec.h:5774
static AVPacket pkt
void * priv_data
Opaque filter-specific private data.
Definition: avcodec.h:5795
const AVBitStreamFilter ff_h264_redundant_pps_bsf
CodedBitstreamContext * input
uint8_t weighted_pred_flag
Definition: cbs_h264.h:204
static int h264_redundant_pps_fixup_slice(H264RedundantPPSContext *ctx, H264RawSliceHeader *slice)
int8_t slice_qp_delta
Definition: cbs_h264.h:417
int ff_cbs_read_packet(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const AVPacket *pkt)
Read the data bitstream from a packet into a fragment, then split into units and decompose.
Definition: cbs.c:239
const char * name
Definition: avcodec.h:5824
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
static int h264_redundant_pps_fixup_pps(H264RedundantPPSContext *ctx, H264RawPPS *pps)
Coded bitstream unit structure.
Definition: cbs.h:64
void * content
Pointer to the decomposed form of this unit.
Definition: cbs.h:101
CodedBitstreamUnit * units
Pointer to an array of units of length nb_units_allocated.
Definition: cbs.h:162
#define av_log(a,...)
void ff_cbs_fragment_free(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag)
Free the units array of a fragment in addition to what ff_cbs_fragment_reset does.
Definition: cbs.c:154
H.264 common definitions.
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce then the filter should push the output frames on the output link immediately As an exception to the previous rule if the input frame is enough to produce several output frames then the filter needs output only at least one per link The additional frames can be left buffered in the filter
#define fail()
Definition: checkasm.h:122
int ff_cbs_write_extradata(CodedBitstreamContext *ctx, AVCodecParameters *par, CodedBitstreamFragment *frag)
Write the bitstream of a fragment to the extradata in codec parameters.
Definition: cbs.c:320
AVFormatContext * ctx
Definition: movenc.c:48
CodedBitstreamContext * output
static void h264_redundant_pps_flush(AVBSFContext *bsf)
static void h264_redundant_pps_close(AVBSFContext *bsf)
Coded bitstream fragment structure, combining one or more units.
Definition: cbs.h:116
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
void ff_cbs_fragment_reset(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag)
Free the units contained in a fragment as well as the fragment&#39;s own data buffer, but not the units a...
Definition: cbs.c:139
static int FUNC() pps(CodedBitstreamContext *ctx, RWContext *rw, H264RawPPS *current)
Context structure for coded bitstream operations.
Definition: cbs.h:168
void ff_cbs_close(CodedBitstreamContext **ctx_ptr)
Close a context and free all internal state.
Definition: cbs.c:113
int ff_cbs_read_extradata(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, const AVCodecParameters *par)
Read the extradata bitstream found in codec parameters into a fragment, then split into units and dec...
Definition: cbs.c:221
CodedBitstreamFragment access_unit
common internal and external API header
static enum AVCodecID codec_ids[]
static enum AVCodecID h264_redundant_pps_codec_ids[]
H264RawSliceHeader header
Definition: cbs_h264.h:430
static int h264_redundant_pps_filter(AVBSFContext *bsf, AVPacket *pkt)
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3982
int8_t pic_init_qp_minus26
Definition: cbs_h264.h:207
This structure stores compressed data.
Definition: avcodec.h:1457
AVCodecParameters * par_in
Parameters of the input stream.
Definition: avcodec.h:5802
int ff_bsf_get_packet_ref(AVBSFContext *ctx, AVPacket *pkt)
Called by bitstream filters to get packet for filtering.
Definition: bsf.c:239
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1473