FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavformat/astcenc.c
Date: 2026-09-15 09:36:26
Exec Total Coverage
Lines: 0 15 0.0%
Functions: 0 2 0.0%
Branches: 0 4 0.0%

Line Branch Exec Source
1 /*
2 * ASTC muxer (.astc container)
3 * Copyright (c) 2026 Jun Zhao
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 /**
23 * @file
24 * ASTC (Adaptive Scalable Texture Compression) muxer.
25 *
26 * The .astc container is a 16-byte header followed by the raw ASTC
27 * bitstream. The header is taken verbatim from the encoder's extradata
28 * (which it publishes in .astc form).
29 */
30
31 #include "avformat.h"
32 #include "avio.h"
33 #include "mux.h"
34
35 #define ASTC_HEADER_SIZE 16
36
37 typedef struct ASTCMuxerContext {
38 int wrote_image;
39 } ASTCMuxerContext;
40
41 static int astc_write_header(AVFormatContext *s)
42 {
43 AVStream *st = s->streams[0];
44
45 if (st->codecpar->extradata_size < ASTC_HEADER_SIZE) {
46 av_log(s, AV_LOG_ERROR, ".astc muxer requires 16-byte extradata "
47 "(block size / dimensions) from the encoder.\n");
48 return AVERROR(EINVAL);
49 }
50
51 avio_write(s->pb, st->codecpar->extradata, ASTC_HEADER_SIZE);
52 return 0;
53 }
54
55 static int astc_write_packet(AVFormatContext *s, AVPacket *pkt)
56 {
57 ASTCMuxerContext *ctx = s->priv_data;
58
59 /* The container holds a single image; FF_OFMT_FLAG_MAX_ONE_OF_EACH only
60 * limits the number of streams, so packets must be rejected here. */
61 if (ctx->wrote_image) {
62 av_log(s, AV_LOG_ERROR,
63 ".astc muxer supports a single image per file.\n");
64 return AVERROR(EINVAL);
65 }
66 ctx->wrote_image = 1;
67
68 avio_write(s->pb, pkt->data, pkt->size);
69 return 0;
70 }
71
72 const FFOutputFormat ff_astc_muxer = {
73 .p.name = "astc",
74 .p.long_name = NULL_IF_CONFIG_SMALL("ASTC (Adaptive Scalable Texture Compression)"),
75 .p.mime_type = "image/astc",
76 .p.extensions = "astc",
77 .p.audio_codec = AV_CODEC_ID_NONE,
78 .p.video_codec = AV_CODEC_ID_ASTC,
79 .p.subtitle_codec = AV_CODEC_ID_NONE,
80 .flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH |
81 FF_OFMT_FLAG_ONLY_DEFAULT_CODECS,
82 .priv_data_size = sizeof(ASTCMuxerContext),
83 .write_header = astc_write_header,
84 .write_packet = astc_write_packet,
85 .p.flags = AVFMT_NOTIMESTAMPS,
86 };
87