summaryrefslogtreecommitdiffstats
path: root/libavformat/format.c
blob: ac9100b6045d383faf809506ca54586103385e41 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/*
 * Format register and lookup
 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "avformat.h"
#include "internal.h"
#include "libavutil/atomic.h"
#include "libavutil/avstring.h"

/**
 * @file
 * Format register and lookup
 */
/** head of registered input format linked list */
static AVInputFormat *first_iformat = NULL;
/** head of registered output format linked list */
static AVOutputFormat *first_oformat = NULL;

AVInputFormat *av_iformat_next(AVInputFormat *f)
{
    if (f)
        return f->next;
    else
        return first_iformat;
}

AVOutputFormat *av_oformat_next(AVOutputFormat *f)
{
    if (f)
        return f->next;
    else
        return first_oformat;
}

void av_register_input_format(AVInputFormat *format)
{
    AVInputFormat **p = &first_iformat;

    format->next = NULL;
    while(avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format))
        p = &(*p)->next;
}

void av_register_output_format(AVOutputFormat *format)
{
    AVOutputFormat **p = &first_oformat;

    format->next = NULL;
    while(avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format))
        p = &(*p)->next;
}

int av_match_ext(const char *filename, const char *extensions)
{
    const char *ext, *p;
    char ext1[32], *q;

    if (!filename)
        return 0;

    ext = strrchr(filename, '.');
    if (ext) {
        ext++;
        p = extensions;
        for (;;) {
            q = ext1;
            while (*p != '\0' && *p != ','  && q - ext1 < sizeof(ext1) - 1)
                *q++ = *p++;
            *q = '\0';
            if (!av_strcasecmp(ext1, ext))
                return 1;
            if (*p == '\0')
                break;
            p++;
        }
    }
    return 0;
}

static int match_format(const char *name, const char *names)
{
    const char *p;
    int len, namelen;

    if (!name || !names)
        return 0;

    namelen = strlen(name);
    while ((p = strchr(names, ','))) {
        len = FFMAX(p - names, namelen);
        if (!av_strncasecmp(name, names, len))
            return 1;
        names = p + 1;
    }
    return !av_strcasecmp(name, names);
}

AVOutputFormat *av_guess_format(const char *short_name, const char *filename,
                                const char *mime_type)
{
    AVOutputFormat *fmt = NULL, *fmt_found;
    int score_max, score;

    /* specific test for image sequences */
#if CONFIG_IMAGE2_MUXER
    if (!short_name && filename &&
        av_filename_number_test(filename) &&
        ff_guess_image2_codec(filename) != AV_CODEC_ID_NONE) {
        return av_guess_format("image2", NULL, NULL);
    }
#endif
    /* Find the proper file type. */
    fmt_found = NULL;
    score_max = 0;
    while ((fmt = av_oformat_next(fmt))) {
        score = 0;
        if (fmt->name && short_name && match_format(short_name, fmt->name))
            score += 100;
        if (fmt->mime_type && mime_type && !strcmp(fmt->mime_type, mime_type))
            score += 10;
        if (filename && fmt->extensions &&
            av_match_ext(filename, fmt->extensions)) {
            score += 5;
        }
        if (score > score_max) {
            score_max = score;
            fmt_found = fmt;
        }
    }
    return fmt_found;
}

enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
                              const char *filename, const char *mime_type,
                              enum AVMediaType type)
{
    if (!strcmp(fmt->name, "segment") || !strcmp(fmt->name, "ssegment")) {
        fmt = av_guess_format(NULL, filename, NULL);
    }

    if (type == AVMEDIA_TYPE_VIDEO) {
        enum AVCodecID codec_id = AV_CODEC_ID_NONE;

#if CONFIG_IMAGE2_MUXER
        if (!strcmp(fmt->name, "image2") || !strcmp(fmt->name, "image2pipe")) {
            codec_id = ff_guess_image2_codec(filename);
        }
#endif
        if (codec_id == AV_CODEC_ID_NONE)
            codec_id = fmt->video_codec;
        return codec_id;
    } else if (type == AVMEDIA_TYPE_AUDIO)
        return fmt->audio_codec;
    else if (type == AVMEDIA_TYPE_SUBTITLE)
        return fmt->subtitle_codec;
    else
        return AV_CODEC_ID_NONE;
}

AVInputFormat *av_find_input_format(const char *short_name)
{
    AVInputFormat *fmt = NULL;
    while ((fmt = av_iformat_next(fmt)))
        if (match_format(short_name, fmt->name))
            return fmt;
    return NULL;
}
OpenPOWER on IntegriCloud