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);
137  av_packet_unref(&w->last_pkt);
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;
151  if (ret < 0)
152  return ret;
153  w->using_webp_anim_encoder |= 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->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 
198  av_packet_unref(&w->last_pkt);
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 };
ENC
#define ENC
Definition: webpenc.c:202
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:404
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
AVOutputFormat::name
const char * name
Definition: avformat.h:496
AVERROR
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
opt.h
WebpContext::using_webp_anim_encoder
int using_webp_anim_encoder
Definition: webpenc.c:33
AVFMT_VARIABLE_FPS
#define AVFMT_VARIABLE_FPS
Format allows variable fps.
Definition: avformat.h:470
WebpContext::frame_count
int frame_count
Definition: webpenc.c:29
WebpContext::wrote_webp_header
int wrote_webp_header
Definition: webpenc.c:32
w
uint8_t w
Definition: llviddspenc.c:38
AVPacket::data
uint8_t * data
Definition: packet.h:373
AVOption
AVOption.
Definition: opt.h:247
ff_webp_muxer
const AVOutputFormat ff_webp_muxer
Definition: webpenc.c:215
avio_wl16
void avio_wl16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:445
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:538
pts
static int64_t pts
Definition: transcode_aac.c:653
loop
static int loop
Definition: ffplay.c:339
options
static const AVOption options[]
Definition: webpenc.c:203
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:126
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
write_trailer
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:98
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
avio_w8
void avio_w8(AVIOContext *s, int b)
Definition: aviobuf.c:193
av_packet_ref
int av_packet_ref(AVPacket *dst, const AVPacket *src)
Setup a new reference to the data described by a given packet.
Definition: avpacket.c:411
webp_deinit
static void webp_deinit(AVFormatContext *s)
Definition: webpenc.c:194
AVPacket::size
int size
Definition: packet.h:374
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:116
avpriv_set_pts_info
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:4799
is_animated_webp_packet
static int is_animated_webp_packet(AVPacket *pkt)
Definition: webpenc.c:54
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:215
avio_wl32
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:365
webp_muxer_class
static const AVClass webp_muxer_class
Definition: webpenc.c:209
write_packet
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
Definition: ffmpeg.c:729
AVOutputFormat
Definition: avformat.h:495
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:366
AVCodecParameters::height
int height
Definition: codec_par.h:127
flush
static int flush(AVFormatContext *s, int trailer, int64_t pts)
Definition: webpenc.c:75
webp_write_packet
static int webp_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: webpenc.c:143
WebpContext::loop
int loop
Definition: webpenc.c:31
AV_CODEC_ID_WEBP
@ AV_CODEC_ID_WEBP
Definition: codec_id.h:222
WebpContext::last_pkt
AVPacket last_pkt
Definition: webpenc.c:30
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:847
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:243
AVClass::class_name
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:71
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:224
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
webp_init
static int webp_init(AVFormatContext *s)
Definition: webpenc.c:36
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
WebpContext
Definition: webpenc.c:27
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
avio_wl24
void avio_wl24(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:457
OFFSET
#define OFFSET(x)
Definition: webpenc.c:201
webp_write_trailer
static int webp_write_trailer(AVFormatContext *s)
Definition: webpenc.c:169