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  int skip = 0;
57  unsigned flags = 0;
58 
59  if (pkt->size < 4)
60  return AVERROR_INVALIDDATA;
61  if (AV_RL32(pkt->data) == AV_RL32("RIFF"))
62  skip = 12;
63  // Safe to do this as a valid WebP bitstream is >=30 bytes.
64  if (pkt->size < skip + 4)
65  return AVERROR_INVALIDDATA;
66  if (AV_RL32(pkt->data + skip) == AV_RL32("VP8X")) {
67  flags |= pkt->data[skip + 4 + 4];
68  }
69 
70  if (flags & 2) // ANIMATION_FLAG is on
71  return 1;
72  return 0;
73 }
74 
75 static int flush(AVFormatContext *s, int trailer, int64_t pts)
76 {
77  WebpContext *w = s->priv_data;
78  AVStream *st = s->streams[0];
79 
80  if (w->last_pkt.size) {
81  int skip = 0;
82  unsigned flags = 0;
83  int vp8x = 0;
84 
85  if (AV_RL32(w->last_pkt.data) == AV_RL32("RIFF"))
86  skip = 12;
87 
88  if (AV_RL32(w->last_pkt.data + skip) == AV_RL32("VP8X")) {
89  flags |= w->last_pkt.data[skip + 4 + 4];
90  vp8x = 1;
91  skip += AV_RL32(w->last_pkt.data + skip + 4) + 8;
92  }
93 
94  if (!w->wrote_webp_header) {
95  avio_write(s->pb, "RIFF\0\0\0\0WEBP", 12);
96  w->wrote_webp_header = 1;
97  if (w->frame_count > 1) // first non-empty packet
98  w->frame_count = 1; // so we don't count previous empty packets.
99  }
100 
101  if (w->frame_count == 1) {
102  if (!trailer) {
103  vp8x = 1;
104  flags |= 2 + 16;
105  }
106 
107  if (vp8x) {
108  avio_write(s->pb, "VP8X", 4);
109  avio_wl32(s->pb, 10);
110  avio_w8(s->pb, flags);
111  avio_wl24(s->pb, 0);
112  avio_wl24(s->pb, st->codecpar->width - 1);
113  avio_wl24(s->pb, st->codecpar->height - 1);
114  }
115  if (!trailer) {
116  avio_write(s->pb, "ANIM", 4);
117  avio_wl32(s->pb, 6);
118  avio_wl32(s->pb, 0xFFFFFFFF);
119  avio_wl16(s->pb, w->loop);
120  }
121  }
122 
123  if (w->frame_count > trailer) {
124  avio_write(s->pb, "ANMF", 4);
125  avio_wl32(s->pb, 16 + w->last_pkt.size - skip);
126  avio_wl24(s->pb, 0);
127  avio_wl24(s->pb, 0);
128  avio_wl24(s->pb, st->codecpar->width - 1);
129  avio_wl24(s->pb, st->codecpar->height - 1);
130  if (w->last_pkt.pts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE) {
131  avio_wl24(s->pb, pts - w->last_pkt.pts);
132  } else
133  avio_wl24(s->pb, w->last_pkt.duration);
134  avio_w8(s->pb, 0);
135  }
136  avio_write(s->pb, w->last_pkt.data + skip, w->last_pkt.size - skip);
138  }
139 
140  return 0;
141 }
142 
144 {
145  WebpContext *w = s->priv_data;
146  int ret;
147 
148  if (!pkt->size)
149  return 0;
150  ret = is_animated_webp_packet(pkt);
151  if (ret < 0)
152  return ret;
154 
155  if (w->using_webp_anim_encoder) {
156  avio_write(s->pb, pkt->data, pkt->size);
157  w->wrote_webp_header = 1; // for good measure
158  } else {
159  int ret;
160  if ((ret = flush(s, 0, pkt->pts)) < 0)
161  return ret;
162  av_packet_ref(&w->last_pkt, pkt);
163  }
164  ++w->frame_count;
165 
166  return 0;
167 }
168 
170 {
171  unsigned filesize;
172  WebpContext *w = s->priv_data;
173 
174  if (w->using_webp_anim_encoder) {
175  if ((w->frame_count > 1) && w->loop) { // Write loop count.
176  avio_seek(s->pb, 42, SEEK_SET);
177  avio_wl16(s->pb, w->loop);
178  }
179  } else {
180  int ret;
181  if ((ret = flush(s, 1, AV_NOPTS_VALUE)) < 0)
182  return ret;
183 
184  filesize = avio_tell(s->pb);
185  avio_seek(s->pb, 4, SEEK_SET);
186  avio_wl32(s->pb, filesize - 8);
187  // Note: without the following, avio only writes 8 bytes to the file.
188  avio_seek(s->pb, filesize, SEEK_SET);
189  }
190 
191  return 0;
192 }
193 
195 {
196  WebpContext *w = s->priv_data;
197 
199 }
200 
201 #define OFFSET(x) offsetof(WebpContext, x)
202 #define ENC AV_OPT_FLAG_ENCODING_PARAM
203 static const AVOption options[] = {
204  { "loop", "Number of times to loop the output: 0 - infinite loop", OFFSET(loop),
205  AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 65535, ENC },
206  { NULL },
207 };
208 
209 static const AVClass webp_muxer_class = {
210  .class_name = "WebP muxer",
211  .item_name = av_default_item_name,
212  .version = LIBAVUTIL_VERSION_INT,
213  .option = options,
214 };
216  .name = "webp",
217  .long_name = NULL_IF_CONFIG_SMALL("WebP"),
218  .extensions = "webp",
219  .priv_data_size = sizeof(WebpContext),
220  .video_codec = AV_CODEC_ID_WEBP,
221  .init = webp_init,
224  .deinit = webp_deinit,
225  .priv_class = &webp_muxer_class,
227 };
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
Definition: ffmpeg.c:729
#define NULL
Definition: coverity.c:32
void avio_wl16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:455
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVOption.
Definition: opt.h:248
#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:4999
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int size
Definition: packet.h:370
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
AVPacket * pkt
Definition: movenc.c:59
int loop
Definition: webpenc.c:31
Format I/O context.
Definition: avformat.h:1247
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:375
int width
Video only.
Definition: codec_par.h:126
AVOptions.
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:387
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1315
uint8_t * data
Definition: packet.h:369
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:225
#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:641
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
static const AVOption options[]
Definition: webpenc.c:203
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:117
int using_webp_anim_encoder
Definition: webpenc.c:33
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1303
static void webp_deinit(AVFormatContext *s)
Definition: webpenc.c:194
uint8_t w
Definition: llviddspenc.c:39
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:98
const char * name
Definition: avformat.h:500
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:209
Stream structure.
Definition: avformat.h:884
AVIOContext * pb
I/O context.
Definition: avformat.h:1289
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:203
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:634
Describe the class of an AVClass context structure.
Definition: log.h:67
void avio_wl24(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:467
static int flush(AVFormatContext *s, int trailer, int64_t pts)
Definition: webpenc.c:75
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:143
AVOutputFormat ff_webp_muxer
Definition: webpenc.c:215
Main libavformat public API header.
#define AVFMT_VARIABLE_FPS
Format allows variable fps.
Definition: avformat.h:465
static int webp_init(AVFormatContext *s)
Definition: webpenc.c:36
void * priv_data
Format private data.
Definition: avformat.h:1275
#define OFFSET(x)
Definition: webpenc.c:201
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1049
static int webp_write_trailer(AVFormatContext *s)
Definition: webpenc.c:169
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:91
This structure stores compressed data.
Definition: packet.h:346
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
#define ENC
Definition: webpenc.c:202
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248