FFmpeg
webpenc.c
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1 /*
2  * webp muxer
3  * Copyright (c) 2014 Michael Niedermayer
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/opt.h"
24 #include "avformat.h"
25 #include "internal.h"
26 
27 typedef struct WebpContext{
28  AVClass *class;
31  int loop;
34 } WebpContext;
35 
37 {
38  AVStream *st;
39 
40  if (s->nb_streams != 1) {
41  av_log(s, AV_LOG_ERROR, "Only exactly 1 stream is supported\n");
42  return AVERROR(EINVAL);
43  }
44  st = s->streams[0];
45  if (st->codecpar->codec_id != AV_CODEC_ID_WEBP) {
46  av_log(s, AV_LOG_ERROR, "Only WebP is supported\n");
47  return AVERROR(EINVAL);
48  }
49  avpriv_set_pts_info(st, 24, 1, 1000);
50 
51  return 0;
52 }
53 
55 {
56  if (pkt->size) {
57  int skip = 0;
58  unsigned flags = 0;
59 
60  if (pkt->size < 4)
61  return 0;
62  if (AV_RL32(pkt->data) == AV_RL32("RIFF"))
63  skip = 12;
64 
65  if (pkt->size < skip + 4)
66  return 0;
67  if (AV_RL32(pkt->data + skip) == AV_RL32("VP8X")) {
68  flags |= pkt->data[skip + 4 + 4];
69  }
70 
71  if (flags & 2) // ANIMATION_FLAG is on
72  return 1;
73  }
74  return 0;
75 }
76 
77 static int flush(AVFormatContext *s, int trailer, int64_t pts)
78 {
79  WebpContext *w = s->priv_data;
80  AVStream *st = s->streams[0];
81 
82  if (w->last_pkt.size) {
83  int skip = 0;
84  unsigned flags = 0;
85  int vp8x = 0;
86 
87  if (w->last_pkt.size < 4)
88  return 0;
89  if (AV_RL32(w->last_pkt.data) == AV_RL32("RIFF"))
90  skip = 12;
91 
92  if (w->last_pkt.size < skip + 4)
93  return 0; // Safe to do this as a valid WebP bitstream is >=30 bytes.
94  if (AV_RL32(w->last_pkt.data + skip) == AV_RL32("VP8X")) {
95  flags |= w->last_pkt.data[skip + 4 + 4];
96  vp8x = 1;
97  skip += AV_RL32(w->last_pkt.data + skip + 4) + 8;
98  }
99 
100  if (!w->wrote_webp_header) {
101  avio_write(s->pb, "RIFF\0\0\0\0WEBP", 12);
102  w->wrote_webp_header = 1;
103  if (w->frame_count > 1) // first non-empty packet
104  w->frame_count = 1; // so we don't count previous empty packets.
105  }
106 
107  if (w->frame_count == 1) {
108  if (!trailer) {
109  vp8x = 1;
110  flags |= 2 + 16;
111  }
112 
113  if (vp8x) {
114  avio_write(s->pb, "VP8X", 4);
115  avio_wl32(s->pb, 10);
116  avio_w8(s->pb, flags);
117  avio_wl24(s->pb, 0);
118  avio_wl24(s->pb, st->codecpar->width - 1);
119  avio_wl24(s->pb, st->codecpar->height - 1);
120  }
121  if (!trailer) {
122  avio_write(s->pb, "ANIM", 4);
123  avio_wl32(s->pb, 6);
124  avio_wl32(s->pb, 0xFFFFFFFF);
125  avio_wl16(s->pb, w->loop);
126  }
127  }
128 
129  if (w->frame_count > trailer) {
130  avio_write(s->pb, "ANMF", 4);
131  avio_wl32(s->pb, 16 + w->last_pkt.size - skip);
132  avio_wl24(s->pb, 0);
133  avio_wl24(s->pb, 0);
134  avio_wl24(s->pb, st->codecpar->width - 1);
135  avio_wl24(s->pb, st->codecpar->height - 1);
136  if (w->last_pkt.pts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE) {
137  avio_wl24(s->pb, pts - w->last_pkt.pts);
138  } else
139  avio_wl24(s->pb, w->last_pkt.duration);
140  avio_w8(s->pb, 0);
141  }
142  avio_write(s->pb, w->last_pkt.data + skip, w->last_pkt.size - skip);
144  }
145 
146  return 0;
147 }
148 
150 {
151  WebpContext *w = s->priv_data;
153 
154  if (w->using_webp_anim_encoder) {
155  avio_write(s->pb, pkt->data, pkt->size);
156  w->wrote_webp_header = 1; // for good measure
157  } else {
158  int ret;
159  if ((ret = flush(s, 0, pkt->pts)) < 0)
160  return ret;
161  av_packet_ref(&w->last_pkt, pkt);
162  }
163  ++w->frame_count;
164 
165  return 0;
166 }
167 
169 {
170  unsigned filesize;
171  WebpContext *w = s->priv_data;
172 
173  if (w->using_webp_anim_encoder) {
174  if ((w->frame_count > 1) && w->loop) { // Write loop count.
175  avio_seek(s->pb, 42, SEEK_SET);
176  avio_wl16(s->pb, w->loop);
177  }
178  } else {
179  int ret;
180  if ((ret = flush(s, 1, AV_NOPTS_VALUE)) < 0)
181  return ret;
182 
183  filesize = avio_tell(s->pb);
184  avio_seek(s->pb, 4, SEEK_SET);
185  avio_wl32(s->pb, filesize - 8);
186  // Note: without the following, avio only writes 8 bytes to the file.
187  avio_seek(s->pb, filesize, SEEK_SET);
188  }
189 
190  return 0;
191 }
192 
193 #define OFFSET(x) offsetof(WebpContext, x)
194 #define ENC AV_OPT_FLAG_ENCODING_PARAM
195 static const AVOption options[] = {
196  { "loop", "Number of times to loop the output: 0 - infinite loop", OFFSET(loop),
197  AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 65535, ENC },
198  { NULL },
199 };
200 
201 static const AVClass webp_muxer_class = {
202  .class_name = "WebP muxer",
203  .item_name = av_default_item_name,
204  .version = LIBAVUTIL_VERSION_INT,
205  .option = options,
206 };
208  .name = "webp",
209  .long_name = NULL_IF_CONFIG_SMALL("WebP"),
210  .extensions = "webp",
211  .priv_data_size = sizeof(WebpContext),
212  .video_codec = AV_CODEC_ID_WEBP,
216  .priv_class = &webp_muxer_class,
218 };
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
Definition: ffmpeg.c:689
#define NULL
Definition: coverity.c:32
void avio_wl16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:472
AVOption.
Definition: opt.h:246
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVPacket last_pkt
Definition: webpenc.c:30
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4892
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3957
int size
Definition: avcodec.h:1478
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
static AVPacket pkt
int loop
Definition: webpenc.c:31
Format I/O context.
Definition: avformat.h:1358
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:372
int width
Video only.
Definition: avcodec.h:4023
AVOptions.
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1495
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
uint8_t * data
Definition: avcodec.h:1477
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:218
#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
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static const AVOption options[]
Definition: webpenc.c:195
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
int using_webp_anim_encoder
Definition: webpenc.c:33
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1414
uint8_t w
Definition: llviddspenc.c:38
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:94
const char * name
Definition: avformat.h:505
static int webp_write_header(AVFormatContext *s)
Definition: webpenc.c:36
int wrote_webp_header
Definition: webpenc.c:32
#define s(width, name)
Definition: cbs_vp9.c:257
static int is_animated_webp_packet(AVPacket *pkt)
Definition: webpenc.c:54
int frame_count
Definition: webpenc.c:29
static const AVClass webp_muxer_class
Definition: webpenc.c:201
Stream structure.
Definition: avformat.h:881
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:196
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
Describe the class of an AVClass context structure.
Definition: log.h:67
void avio_wl24(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:484
static int flush(AVFormatContext *s, int trailer, int64_t pts)
Definition: webpenc.c:77
static int64_t pts
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int webp_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: webpenc.c:149
AVOutputFormat ff_webp_muxer
Definition: webpenc.c:207
Main libavformat public API header.
#define AVFMT_VARIABLE_FPS
Format allows variable fps.
Definition: avformat.h:470
void * priv_data
Format private data.
Definition: avformat.h:1386
#define OFFSET(x)
Definition: webpenc.c:193
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:337
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
static int webp_write_trailer(AVFormatContext *s)
Definition: webpenc.c:168
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
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1454
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1470
#define ENC
Definition: webpenc.c:194
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248