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 "bsf_internal.h"
26 #include "cbs.h"
27 #include "cbs_h264.h"
28 #include "h264.h"
29 
30 
31 typedef struct H264RedundantPPSContext {
34 
36 
41 
42 
44  H264RawPPS *pps)
45 {
46  // Record the current value of pic_init_qp in order to fix up
47  // following slices, then overwrite with the global value.
49  pps->pic_init_qp_minus26 = ctx->global_pic_init_qp - 26;
50 
51  // Some PPSs have this set, so it must be set in all of them.
52  // (Slices which do not use such a PPS on input will still have
53  // *_weight_l*flag as zero and therefore write equivalently.)
54  pps->weighted_pred_flag = 1;
55 
56  return 0;
57 }
58 
60  H264RawSliceHeader *slice)
61 {
62  int qp;
63 
64  qp = ctx->current_pic_init_qp + slice->slice_qp_delta;
65  slice->slice_qp_delta = qp - ctx->global_pic_init_qp;
66 
67  return 0;
68 }
69 
71 {
74  int au_has_sps;
75  int err, i;
76 
77  err = ff_bsf_get_packet_ref(bsf, pkt);
78  if (err < 0)
79  return err;
80 
81  err = ff_cbs_read_packet(ctx->input, au, pkt);
82  if (err < 0)
83  goto fail;
84 
85  au_has_sps = 0;
86  for (i = 0; i < au->nb_units; i++) {
87  CodedBitstreamUnit *nal = &au->units[i];
88 
89  if (nal->type == H264_NAL_SPS)
90  au_has_sps = 1;
91  if (nal->type == H264_NAL_PPS) {
92  err = h264_redundant_pps_fixup_pps(ctx, nal->content);
93  if (err < 0)
94  goto fail;
95  if (!au_has_sps) {
96  av_log(bsf, AV_LOG_VERBOSE, "Deleting redundant PPS "
97  "at %"PRId64".\n", pkt->pts);
98  ff_cbs_delete_unit(ctx->input, au, i);
99  i--;
100  continue;
101  }
102  }
103  if (nal->type == H264_NAL_SLICE ||
104  nal->type == H264_NAL_IDR_SLICE) {
105  H264RawSlice *slice = nal->content;
107  }
108  }
109 
110  err = ff_cbs_write_packet(ctx->output, pkt, au);
111  if (err < 0)
112  goto fail;
113 
114  err = 0;
115 fail:
116  ff_cbs_fragment_reset(ctx->output, au);
117  if (err < 0)
118  av_packet_unref(pkt);
119 
120  return err;
121 }
122 
124 {
127  int err, i;
128 
129  err = ff_cbs_init(&ctx->input, AV_CODEC_ID_H264, bsf);
130  if (err < 0)
131  return err;
132 
133  err = ff_cbs_init(&ctx->output, AV_CODEC_ID_H264, bsf);
134  if (err < 0)
135  return err;
136 
137  ctx->global_pic_init_qp = 26;
138 
139  if (bsf->par_in->extradata) {
140  err = ff_cbs_read_extradata(ctx->input, au, bsf->par_in);
141  if (err < 0) {
142  av_log(bsf, AV_LOG_ERROR, "Failed to read extradata.\n");
143  goto fail;
144  }
145 
146  for (i = 0; i < au->nb_units; i++) {
147  if (au->units[i].type == H264_NAL_PPS) {
148  err = h264_redundant_pps_fixup_pps(ctx, au->units[i].content);
149  if (err < 0)
150  goto fail;
151  }
152  }
153 
155  err = ff_cbs_write_extradata(ctx->output, bsf->par_out, au);
156  if (err < 0) {
157  av_log(bsf, AV_LOG_ERROR, "Failed to write extradata.\n");
158  goto fail;
159  }
160  }
161 
162  err = 0;
163 fail:
164  ff_cbs_fragment_reset(ctx->output, au);
165  return err;
166 }
167 
169 {
172 }
173 
175 {
177 
179  ff_cbs_close(&ctx->input);
180  ff_cbs_close(&ctx->output);
181 }
182 
185 };
186 
188  .name = "h264_redundant_pps",
189  .priv_data_size = sizeof(H264RedundantPPSContext),
192  .close = &h264_redundant_pps_close,
195 };
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: bsf.h:83
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:401
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:799
CodedBitstreamUnitType type
Codec-specific type of this unit.
Definition: cbs.h:68
The bitstream filter state.
Definition: bsf.h:49
static AVPacket pkt
void * priv_data
Opaque filter-specific private data.
Definition: bsf.h:70
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:242
const char * name
Definition: bsf.h:99
#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:157
H.264 common definitions.
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:46
#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:123
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:376
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:604
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:142
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:115
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:224
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: codec_par.h:74
int8_t pic_init_qp_minus26
Definition: cbs_h264.h:207
This structure stores compressed data.
Definition: packet.h:332
AVCodecParameters * par_in
Parameters of the input stream.
Definition: bsf.h:77
int ff_bsf_get_packet_ref(AVBSFContext *ctx, AVPacket *pkt)
Called by bitstream filters to get packet for filtering.
Definition: bsf.c:249
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:348