FFmpeg  4.2.3
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:5797
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:796
CodedBitstreamUnitType type
Codec-specific type of this unit.
Definition: cbs.h:68
The bitstream filter state.
Definition: avcodec.h:5763
static AVPacket pkt
void * priv_data
Opaque filter-specific private data.
Definition: avcodec.h:5784
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
static void filter(int16_t *output, ptrdiff_t out_stride, int16_t *low, ptrdiff_t low_stride, int16_t *high, ptrdiff_t high_stride, int len, int clip)
Definition: cfhd.c:153
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: avcodec.h:5813
#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: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
#define fail()
Definition: checkasm.h:120
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: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: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: avcodec.h:3971
int8_t pic_init_qp_minus26
Definition: cbs_h264.h:207
This structure stores compressed data.
Definition: avcodec.h:1454
AVCodecParameters * par_in
Parameters of the input stream.
Definition: avcodec.h:5791
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:1470