FFmpeg
av1_frame_split_bsf.c
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1 /*
2  * Copyright (c) 2019 James Almer <jamrial@gmail.com>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * This bitstream filter splits AV1 Temporal Units into packets containing
24  * just one frame, plus any leading and trailing OBUs that may be present at
25  * the beginning or end, respectively.
26  *
27  * Temporal Units already containing only one frame will be passed through
28  * unchanged. When splitting can't be performed, the Temporal Unit will be
29  * passed through containing only the remaining OBUs starting from the first
30  * one after the last successfully split frame.
31  */
32 
33 #include "libavutil/avassert.h"
34 
35 #include "avcodec.h"
36 #include "bsf.h"
37 #include "cbs.h"
38 #include "cbs_av1.h"
39 
40 typedef struct AV1FSplitContext {
44 
45  int nb_frames;
46  int cur_frame;
50 
52 {
55  int i, ret;
56  int split = !!s->buffer_pkt->data;
57 
58  if (!s->buffer_pkt->data) {
59  int nb_frames = 0;
60 
61  ret = ff_bsf_get_packet_ref(ctx, s->buffer_pkt);
62  if (ret < 0)
63  return ret;
64 
65  ret = ff_cbs_read_packet(s->cbc, td, s->buffer_pkt);
66  if (ret < 0) {
67  av_log(ctx, AV_LOG_WARNING, "Failed to parse temporal unit.\n");
68  goto passthrough;
69  }
70 
71  for (i = 0; i < td->nb_units; i++) {
72  CodedBitstreamUnit *unit = &td->units[i];
73 
74  if (unit->type == AV1_OBU_FRAME ||
75  unit->type == AV1_OBU_FRAME_HEADER)
76  nb_frames++;
77  else if (unit->type == AV1_OBU_TILE_LIST) {
78  av_log(ctx, AV_LOG_VERBOSE, "Large scale tiles are unsupported.\n");
79  goto passthrough;
80  }
81  }
82  if (nb_frames > 1) {
83  s->cur_frame = 0;
84  s->cur_frame_idx = s->last_frame_idx = 0;
85  s->nb_frames = nb_frames;
86  split = 1;
87  }
88  }
89 
90  if (split) {
92  int cur_frame_type = -1, size = 0;
93 
94  for (i = s->cur_frame_idx; i < td->nb_units; i++) {
95  CodedBitstreamUnit *unit = &td->units[i];
96 
97  size += unit->data_size;
98  if (unit->type == AV1_OBU_FRAME) {
99  AV1RawOBU *obu = unit->content;
100 
101  if (frame) {
102  av_log(ctx, AV_LOG_WARNING, "Frame OBU found when Tile data for a "
103  "previous frame was expected.\n");
104  goto passthrough;
105  }
106 
107  frame = &obu->obu.frame.header;
108  cur_frame_type = obu->header.obu_type;
110  s->cur_frame_idx = i + 1;
111  s->cur_frame++;
112 
113  // split here unless it's the last frame, in which case
114  // include every trailing OBU
115  if (s->cur_frame < s->nb_frames)
116  break;
117  } else if (unit->type == AV1_OBU_FRAME_HEADER) {
118  AV1RawOBU *obu = unit->content;
119 
120  if (frame) {
121  av_log(ctx, AV_LOG_WARNING, "Frame Header OBU found when Tile data for a "
122  "previous frame was expected.\n");
123  goto passthrough;
124  }
125 
126  frame = &obu->obu.frame_header;
127  cur_frame_type = obu->header.obu_type;
129  s->cur_frame++;
130 
131  // split here if show_existing_frame unless it's the last
132  // frame, in which case include every trailing OBU
133  if (frame->show_existing_frame &&
134  s->cur_frame < s->nb_frames) {
135  s->cur_frame_idx = i + 1;
136  break;
137  }
138  } else if (unit->type == AV1_OBU_TILE_GROUP) {
139  AV1RawOBU *obu = unit->content;
140  AV1RawTileGroup *group = &obu->obu.tile_group;
141 
142  if (!frame || cur_frame_type != AV1_OBU_FRAME_HEADER) {
143  av_log(ctx, AV_LOG_WARNING, "Unexpected Tile Group OBU found before a "
144  "Frame Header.\n");
145  goto passthrough;
146  }
147 
148  if ((group->tg_end == (frame->tile_cols * frame->tile_rows) - 1) &&
149  // include every trailing OBU with the last frame
150  s->cur_frame < s->nb_frames) {
151  s->cur_frame_idx = i + 1;
152  break;
153  }
154  }
155  }
156  av_assert0(frame && s->cur_frame <= s->nb_frames);
157 
158  ret = av_packet_ref(out, s->buffer_pkt);
159  if (ret < 0)
160  goto fail;
161 
162  out->data = (uint8_t *)td->units[s->last_frame_idx].data;
163  out->size = size;
164 
165  // skip the frame in the buffer packet if it's split successfully, so it's not present
166  // if the packet is passed through in case of failure when splitting another frame.
167  s->buffer_pkt->data += size;
168  s->buffer_pkt->size -= size;
169 
170  if (!frame->show_existing_frame && !frame->show_frame)
171  out->pts = AV_NOPTS_VALUE;
172 
173  if (s->cur_frame == s->nb_frames) {
175  ff_cbs_fragment_reset(s->cbc, td);
176  }
177 
178  return 0;
179  }
180 
181 passthrough:
183 
184  ret = 0;
185 fail:
186  if (ret < 0) {
187  av_packet_unref(out);
189  }
190  ff_cbs_fragment_reset(s->cbc, td);
191 
192  return ret;
193 }
194 
201 };
202 
204 {
205  AV1FSplitContext *s = ctx->priv_data;
207  int ret;
208 
210  if (!s->buffer_pkt)
211  return AVERROR(ENOMEM);
212 
213  ret = ff_cbs_init(&s->cbc, AV_CODEC_ID_AV1, ctx);
214  if (ret < 0)
215  return ret;
216 
219 
220  if (!ctx->par_in->extradata_size)
221  return 0;
222 
223  ret = ff_cbs_read_extradata(s->cbc, td, ctx->par_in);
224  if (ret < 0)
225  av_log(ctx, AV_LOG_WARNING, "Failed to parse extradata.\n");
226 
227  ff_cbs_fragment_reset(s->cbc, td);
228 
229  return 0;
230 }
231 
233 {
234  AV1FSplitContext *s = ctx->priv_data;
235 
238 }
239 
241 {
242  AV1FSplitContext *s = ctx->priv_data;
243 
246  ff_cbs_close(&s->cbc);
247 }
248 
249 static const enum AVCodecID av1_frame_split_codec_ids[] = {
251 };
252 
254  .name = "av1_frame_split",
255  .priv_data_size = sizeof(AV1FSplitContext),
258  .close = av1_frame_split_close,
261 };
#define NULL
Definition: coverity.c:32
int nb_units
Number of units in this fragment.
Definition: cbs.h:147
static void flush(AVCodecContext *avctx)
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
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
CodedBitstreamUnitType type
Codec-specific type of this unit.
Definition: cbs.h:68
The bitstream filter state.
Definition: avcodec.h:5774
int size
Definition: avcodec.h:1481
static void av1_frame_split_flush(AVBSFContext *ctx)
void * priv_data
Opaque filter-specific private data.
Definition: avcodec.h:5795
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
uint16_t tile_rows
Definition: cbs_av1.h:194
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:62
uint8_t
uint32_t CodedBitstreamUnitType
The codec-specific type of a bitstream unit.
Definition: cbs.h:43
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
uint8_t * data
Definition: avcodec.h:1480
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:655
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
Coded bitstream unit structure.
Definition: cbs.h:64
ptrdiff_t size
Definition: opengl_enc.c:100
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
uint8_t * data
Pointer to the directly-parsable bitstream form of this unit.
Definition: cbs.h:75
#define av_log(a,...)
int av_packet_ref(AVPacket *dst, const AVPacket *src)
Setup a new reference to the data described by a given packet.
Definition: avpacket.c:608
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
static const CodedBitstreamUnitType decompose_unit_types[]
#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 td
Definition: regdef.h:70
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
union AV1RawOBU::@48 obu
AV1RawFrame frame
Definition: cbs_av1.h:395
simple assert() macros that are a bit more flexible than ISO C assert().
#define fail()
Definition: checkasm.h:122
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3986
static char * split(char *message, char delim)
Definition: af_channelmap.c:81
CodedBitstreamContext * cbc
AV1RawOBUHeader header
Definition: cbs_av1.h:388
AVFormatContext * ctx
Definition: movenc.c:48
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
#define FF_ARRAY_ELEMS(a)
if(ret)
static enum AVCodecID av1_frame_split_codec_ids[]
static int av1_frame_split_init(AVBSFContext *ctx)
Libavcodec external API header.
int nb_decompose_unit_types
Length of the decompose_unit_types array.
Definition: cbs.h:201
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
static void av1_frame_split_close(AVBSFContext *ctx)
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
Context structure for coded bitstream operations.
Definition: cbs.h:168
uint8_t show_existing_frame
Definition: cbs_av1.h:134
void ff_cbs_close(CodedBitstreamContext **ctx_ptr)
Close a context and free all internal state.
Definition: cbs.c:113
uint8_t obu_type
Definition: cbs_av1.h:31
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
uint16_t tile_cols
Definition: cbs_av1.h:193
const AVBitStreamFilter ff_av1_frame_split_bsf
static enum AVCodecID codec_ids[]
CodedBitstreamUnitType * decompose_unit_types
Array of unit types which should be decomposed when reading.
Definition: cbs.h:197
CodedBitstreamFragment temporal_unit
uint16_t tg_end
Definition: cbs_av1.h:294
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.c:51
AV1RawTileGroup tile_group
Definition: cbs_av1.h:396
AV1RawFrameHeader frame_header
Definition: cbs_av1.h:394
FILE * out
Definition: movenc.c:54
uint8_t show_frame
Definition: cbs_av1.h:140
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AV1RawFrameHeader header
Definition: cbs_av1.h:300
static int av1_frame_split_filter(AVBSFContext *ctx, AVPacket *out)
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
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
size_t data_size
The number of bytes in the bitstream (including any padding bits in the final byte).
Definition: cbs.h:80