FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavformat/webpenc.c
Date: 2026-10-02 18:58:27
Exec Total Coverage
Lines: 0 111 0.0%
Functions: 0 5 0.0%
Branches: 0 68 0.0%

Line Branch Exec Source
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 "libavcodec/bytestream.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "mux.h"
28
29 typedef struct WebpContext{
30 AVClass *class;
31 int frame_count;
32 AVPacket *last_pkt; /* Not owned by us */
33 int loop;
34 int wrote_webp_header;
35 int using_webp_anim_encoder;
36 } WebpContext;
37
38 ✗ static int webp_init(AVFormatContext *s)
39 {
40 ✗ WebpContext *const w = s->priv_data;
41 ✗ AVStream *st = s->streams[0];
42
43 ✗ w->last_pkt = ffformatcontext(s)->pkt;
44
45 ✗ avpriv_set_pts_info(st, 24, 1, 1000);
46
47 ✗ return 0;
48 }
49
50 ✗ static int is_animated_webp_packet(AVPacket *pkt)
51 {
52 ✗ int skip = 0;
53 ✗ unsigned flags = 0;
54
55 ✗ if (pkt->size < 4)
56 ✗ return AVERROR_INVALIDDATA;
57 ✗ if (AV_RL32(pkt->data) == AV_RL32("RIFF"))
58 ✗ skip = 12;
59 // Safe to do this as a valid WebP bitstream is >=30 bytes.
60 ✗ if (pkt->size < skip + 4)
61 ✗ return AVERROR_INVALIDDATA;
62 ✗ if (AV_RL32(pkt->data + skip) == AV_RL32("VP8X")) {
63 ✗ if (pkt->size < skip + 9)
64 ✗ return AVERROR_INVALIDDATA;
65 ✗ flags |= pkt->data[skip + 4 + 4];
66 }
67
68 ✗ if (flags & 2) // ANIMATION_FLAG is on
69 ✗ return 1;
70 ✗ return 0;
71 }
72
73 /**
74 * Returns 1 if it has written a RIFF header with a correct length field
75 */
76 ✗ static int flush(AVFormatContext *s, int trailer, int64_t pts)
77 {
78 ✗ WebpContext *w = s->priv_data;
79 ✗ AVStream *st = s->streams[0];
80 uint8_t buf[12 /* RIFF+WEBP */ + 18 /* VP8X */ +
81 ✗ 14 /* ANIM */ + 24 /* ANMF */], *bufp = buf;
82 ✗ int writing_webp_header = 0, skip = 0;
83 ✗ unsigned flags = 0;
84 ✗ int vp8x = 0;
85
86 ✗ if (!w->last_pkt->size)
87 ✗ return 0;
88
89 ✗ if (AV_RL32(w->last_pkt->data) == AV_RL32("RIFF"))
90 ✗ skip = 12;
91
92 ✗ if (AV_RL32(w->last_pkt->data + skip) == AV_RL32("VP8X")) {
93 ✗ int64_t vp8x_end = skip + 8 + (int64_t)AV_RL32(w->last_pkt->data + skip + 4);
94 ✗ if (vp8x_end > w->last_pkt->size)
95 ✗ return AVERROR_INVALIDDATA;
96 ✗ flags |= w->last_pkt->data[skip + 4 + 4];
97 ✗ vp8x = 1;
98 ✗ skip = vp8x_end;
99 }
100
101 ✗ if (!w->wrote_webp_header) {
102 ✗ bytestream_put_le32(&bufp, MKTAG('R', 'I', 'F', 'F'));
103 ✗ bytestream_put_le32(&bufp, 0); /* Size to be patched later */
104 ✗ bytestream_put_le32(&bufp, MKTAG('W', 'E', 'B', 'P'));
105 ✗ writing_webp_header = 1;
106 ✗ w->wrote_webp_header = 1;
107 ✗ if (w->frame_count > 1) // first non-empty packet
108 ✗ w->frame_count = 1; // so we don't count previous empty packets.
109 }
110
111 ✗ if (w->frame_count == 1) {
112 ✗ if (!trailer) {
113 ✗ vp8x = 1;
114 ✗ flags |= 2 + 16;
115 }
116
117 ✗ if (vp8x) {
118 ✗ bytestream_put_le32(&bufp, MKTAG('V', 'P', '8', 'X'));
119 ✗ bytestream_put_le32(&bufp, 10);
120 ✗ bytestream_put_byte(&bufp, flags);
121 ✗ bytestream_put_le24(&bufp, 0);
122 ✗ bytestream_put_le24(&bufp, st->codecpar->width - 1);
123 ✗ bytestream_put_le24(&bufp, st->codecpar->height - 1);
124 }
125 ✗ if (!trailer) {
126 ✗ bytestream_put_le32(&bufp, MKTAG('A', 'N', 'I', 'M'));
127 ✗ bytestream_put_le32(&bufp, 6);
128 ✗ bytestream_put_le32(&bufp, 0xFFFFFFFF);
129 ✗ bytestream_put_le16(&bufp, w->loop);
130 }
131 }
132
133 ✗ if (w->frame_count > trailer) {
134 ✗ bytestream_put_le32(&bufp, MKTAG('A', 'N', 'M', 'F'));
135 ✗ bytestream_put_le32(&bufp, 16 + w->last_pkt->size - skip);
136 ✗ bytestream_put_le24(&bufp, 0);
137 ✗ bytestream_put_le24(&bufp, 0);
138 ✗ bytestream_put_le24(&bufp, st->codecpar->width - 1);
139 ✗ bytestream_put_le24(&bufp, st->codecpar->height - 1);
140 ✗ if (w->last_pkt->pts != AV_NOPTS_VALUE && pts != AV_NOPTS_VALUE) {
141 ✗ bytestream_put_le24(&bufp, pts - w->last_pkt->pts);
142 } else
143 ✗ bytestream_put_le24(&bufp, w->last_pkt->duration);
144 ✗ bytestream_put_byte(&bufp, 0);
145 }
146 ✗ if (trailer && writing_webp_header)
147 ✗ AV_WL32(buf + 4, bufp - (buf + 8) + w->last_pkt->size - skip);
148 ✗ avio_write(s->pb, buf, bufp - buf);
149 ✗ avio_write(s->pb, w->last_pkt->data + skip, w->last_pkt->size - skip);
150 ✗ av_packet_unref(w->last_pkt);
151
152 ✗ return trailer && writing_webp_header;
153 }
154
155 ✗ static int webp_write_packet(AVFormatContext *s, AVPacket *pkt)
156 {
157 ✗ WebpContext *w = s->priv_data;
158 int ret;
159
160 ✗ if (!pkt->size)
161 ✗ return 0;
162 ✗ ret = is_animated_webp_packet(pkt);
163 ✗ if (ret < 0)
164 ✗ return ret;
165 ✗ w->using_webp_anim_encoder |= ret;
166
167 ✗ if (w->using_webp_anim_encoder) {
168 ✗ avio_write(s->pb, pkt->data, pkt->size);
169 ✗ w->wrote_webp_header = 1; // for good measure
170 } else {
171 ✗ if ((ret = flush(s, 0, pkt->pts)) < 0)
172 ✗ return ret;
173 ✗ av_packet_ref(w->last_pkt, pkt);
174 }
175 ✗ ++w->frame_count;
176
177 ✗ return 0;
178 }
179
180 ✗ static int webp_write_trailer(AVFormatContext *s)
181 {
182 unsigned filesize;
183 ✗ WebpContext *w = s->priv_data;
184
185 ✗ if (w->using_webp_anim_encoder) {
186 ✗ if (w->loop) { // Write loop count.
187 ✗ if (avio_seek(s->pb, 42, SEEK_SET) == 42)
188 ✗ avio_wl16(s->pb, w->loop);
189 }
190 } else {
191 int ret;
192 ✗ if ((ret = flush(s, 1, AV_NOPTS_VALUE)) < 0)
193 ✗ return ret;
194
195 ✗ if (!ret) {
196 ✗ filesize = avio_tell(s->pb);
197 ✗ if (filesize >= 8 && avio_seek(s->pb, 4, SEEK_SET) == 4) {
198 ✗ avio_wl32(s->pb, filesize - 8);
199 // Note: without the following, avio only writes 8 bytes to the file.
200 ✗ avio_seek(s->pb, filesize, SEEK_SET);
201 }
202 }
203 }
204
205 ✗ return 0;
206 }
207
208 #define OFFSET(x) offsetof(WebpContext, x)
209 #define ENC AV_OPT_FLAG_ENCODING_PARAM
210 static const AVOption options[] = {
211 { "loop", "Number of times to loop the output: 0 - infinite loop", OFFSET(loop),
212 AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 65535, ENC },
213 { NULL },
214 };
215
216 static const AVClass webp_muxer_class = {
217 .class_name = "WebP muxer",
218 .item_name = av_default_item_name,
219 .version = LIBAVUTIL_VERSION_INT,
220 .option = options,
221 };
222 const FFOutputFormat ff_webp_muxer = {
223 .p.name = "webp",
224 .p.long_name = NULL_IF_CONFIG_SMALL("WebP"),
225 .p.extensions = "webp",
226 .priv_data_size = sizeof(WebpContext),
227 .p.video_codec = AV_CODEC_ID_WEBP,
228 .p.audio_codec = AV_CODEC_ID_NONE,
229 .p.subtitle_codec = AV_CODEC_ID_NONE,
230 .init = webp_init,
231 .write_packet = webp_write_packet,
232 .write_trailer = webp_write_trailer,
233 .p.priv_class = &webp_muxer_class,
234 .p.flags = AVFMT_VARIABLE_FPS,
235 .flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH |
236 FF_OFMT_FLAG_ONLY_DEFAULT_CODECS,
237 };
238