ffmpeg/libavformat/format.c
Andreas Rheinhardt 790f793844 avutil/common: Don't auto-include mem.h
There are lots of files that don't need it: The number of object
files that actually need it went down from 2011 to 884 here.

Keep it for external users in order to not cause breakages.

Also improve the other headers a bit while just at it.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-03-31 00:08:43 +01:00

350 lines
11 KiB
C

/*
* 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 "config_components.h"
#include "libavutil/avstring.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"
#include "avio_internal.h"
#include "avformat.h"
#include "demux.h"
#include "id3v2.h"
#include "internal.h"
#include "url.h"
/**
* @file
* Format register and lookup
*/
int av_match_ext(const char *filename, const char *extensions)
{
const char *ext;
if (!filename)
return 0;
ext = strrchr(filename, '.');
if (ext)
return av_match_name(ext + 1, extensions);
return 0;
}
int ff_match_url_ext(const char *url, const char *extensions)
{
const char *ext;
URLComponents uc;
int ret;
char scratchpad[128];
if (!url)
return 0;
ret = ff_url_decompose(&uc, url, NULL);
if (ret < 0 || !URL_COMPONENT_HAVE(uc, scheme))
return ret;
for (ext = uc.query; *ext != '.' && ext > uc.path; ext--)
;
if (*ext != '.')
return 0;
if (uc.query - ext > sizeof(scratchpad))
return AVERROR(ENOMEM); //not enough memory in our scratchpad
av_strlcpy(scratchpad, ext + 1, uc.query - ext);
return av_match_name(scratchpad, extensions);
}
const AVOutputFormat *av_guess_format(const char *short_name, const char *filename,
const char *mime_type)
{
const AVOutputFormat *fmt = NULL;
const AVOutputFormat *fmt_found = NULL;
void *i = 0;
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. */
score_max = 0;
while ((fmt = av_muxer_iterate(&i))) {
score = 0;
if (fmt->name && short_name && av_match_name(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(const AVOutputFormat *fmt, const char *short_name,
const char *filename, const char *mime_type,
enum AVMediaType type)
{
if (av_match_name("segment", fmt->name) || av_match_name("ssegment", fmt->name)) {
const AVOutputFormat *fmt2 = av_guess_format(NULL, filename, NULL);
if (fmt2)
fmt = fmt2;
}
if (type == AVMEDIA_TYPE_VIDEO) {
enum AVCodecID codec_id = AV_CODEC_ID_NONE;
#if CONFIG_IMAGE2_MUXER || CONFIG_IMAGE2PIPE_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;
}
const AVInputFormat *av_find_input_format(const char *short_name)
{
const AVInputFormat *fmt = NULL;
void *i = 0;
while ((fmt = av_demuxer_iterate(&i)))
if (av_match_name(short_name, fmt->name))
return fmt;
return NULL;
}
const AVInputFormat *av_probe_input_format3(const AVProbeData *pd,
int is_opened, int *score_ret)
{
AVProbeData lpd = *pd;
const AVInputFormat *fmt1 = NULL;
const AVInputFormat *fmt = NULL;
int score, score_max = 0;
void *i = 0;
const static uint8_t zerobuffer[AVPROBE_PADDING_SIZE];
enum nodat {
NO_ID3,
ID3_ALMOST_GREATER_PROBE,
ID3_GREATER_PROBE,
ID3_GREATER_MAX_PROBE,
} nodat = NO_ID3;
if (!lpd.buf)
lpd.buf = (unsigned char *) zerobuffer;
if (lpd.buf_size > 10 && ff_id3v2_match(lpd.buf, ID3v2_DEFAULT_MAGIC)) {
int id3len = ff_id3v2_tag_len(lpd.buf);
if (lpd.buf_size > id3len + 16) {
if (lpd.buf_size < 2LL*id3len + 16)
nodat = ID3_ALMOST_GREATER_PROBE;
lpd.buf += id3len;
lpd.buf_size -= id3len;
} else if (id3len >= PROBE_BUF_MAX) {
nodat = ID3_GREATER_MAX_PROBE;
} else
nodat = ID3_GREATER_PROBE;
}
while ((fmt1 = av_demuxer_iterate(&i))) {
if (fmt1->flags & AVFMT_EXPERIMENTAL)
continue;
if (!is_opened == !(fmt1->flags & AVFMT_NOFILE) && strcmp(fmt1->name, "image2"))
continue;
score = 0;
if (ffifmt(fmt1)->read_probe) {
score = ffifmt(fmt1)->read_probe(&lpd);
if (score)
av_log(NULL, AV_LOG_TRACE, "Probing %s score:%d size:%d\n", fmt1->name, score, lpd.buf_size);
if (fmt1->extensions && av_match_ext(lpd.filename, fmt1->extensions)) {
switch (nodat) {
case NO_ID3:
score = FFMAX(score, 1);
break;
case ID3_GREATER_PROBE:
case ID3_ALMOST_GREATER_PROBE:
score = FFMAX(score, AVPROBE_SCORE_EXTENSION / 2 - 1);
break;
case ID3_GREATER_MAX_PROBE:
score = FFMAX(score, AVPROBE_SCORE_EXTENSION);
break;
}
}
} else if (fmt1->extensions) {
if (av_match_ext(lpd.filename, fmt1->extensions))
score = AVPROBE_SCORE_EXTENSION;
}
if (av_match_name(lpd.mime_type, fmt1->mime_type)) {
if (AVPROBE_SCORE_MIME > score) {
av_log(NULL, AV_LOG_DEBUG, "Probing %s score:%d increased to %d due to MIME type\n", fmt1->name, score, AVPROBE_SCORE_MIME);
score = AVPROBE_SCORE_MIME;
}
}
if (score > score_max) {
score_max = score;
fmt = fmt1;
} else if (score == score_max)
fmt = NULL;
}
if (nodat == ID3_GREATER_PROBE)
score_max = FFMIN(AVPROBE_SCORE_EXTENSION / 2 - 1, score_max);
*score_ret = score_max;
return fmt;
}
const AVInputFormat *av_probe_input_format2(const AVProbeData *pd,
int is_opened, int *score_max)
{
int score_ret;
const AVInputFormat *fmt = av_probe_input_format3(pd, is_opened, &score_ret);
if (score_ret > *score_max) {
*score_max = score_ret;
return fmt;
} else
return NULL;
}
const AVInputFormat *av_probe_input_format(const AVProbeData *pd, int is_opened)
{
int score = 0;
return av_probe_input_format2(pd, is_opened, &score);
}
int av_probe_input_buffer2(AVIOContext *pb, const AVInputFormat **fmt,
const char *filename, void *logctx,
unsigned int offset, unsigned int max_probe_size)
{
AVProbeData pd = { filename ? filename : "" };
uint8_t *buf = NULL;
int ret = 0, probe_size, buf_offset = 0;
int score = 0;
int ret2;
int eof = 0;
if (!max_probe_size)
max_probe_size = PROBE_BUF_MAX;
else if (max_probe_size < PROBE_BUF_MIN) {
av_log(logctx, AV_LOG_ERROR,
"Specified probe size value %u cannot be < %u\n", max_probe_size, PROBE_BUF_MIN);
return AVERROR(EINVAL);
}
if (offset >= max_probe_size)
return AVERROR(EINVAL);
if (pb->av_class) {
uint8_t *mime_type_opt = NULL;
char *semi;
av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type_opt);
pd.mime_type = (const char *)mime_type_opt;
semi = pd.mime_type ? strchr(pd.mime_type, ';') : NULL;
if (semi) {
*semi = '\0';
}
}
for (probe_size = PROBE_BUF_MIN; probe_size <= max_probe_size && !*fmt && !eof;
probe_size = FFMIN(probe_size << 1,
FFMAX(max_probe_size, probe_size + 1))) {
score = probe_size < max_probe_size ? AVPROBE_SCORE_RETRY : 0;
/* Read probe data. */
if ((ret = av_reallocp(&buf, probe_size + AVPROBE_PADDING_SIZE)) < 0)
goto fail;
if ((ret = avio_read(pb, buf + buf_offset,
probe_size - buf_offset)) < 0) {
/* Fail if error was not end of file, otherwise, lower score. */
if (ret != AVERROR_EOF)
goto fail;
score = 0;
ret = 0; /* error was end of file, nothing read */
eof = 1;
}
buf_offset += ret;
if (buf_offset < offset)
continue;
pd.buf_size = buf_offset - offset;
pd.buf = &buf[offset];
memset(pd.buf + pd.buf_size, 0, AVPROBE_PADDING_SIZE);
/* Guess file format. */
*fmt = av_probe_input_format2(&pd, 1, &score);
if (*fmt) {
/* This can only be true in the last iteration. */
if (score <= AVPROBE_SCORE_RETRY) {
av_log(logctx, AV_LOG_WARNING,
"Format %s detected only with low score of %d, "
"misdetection possible!\n", (*fmt)->name, score);
} else
av_log(logctx, AV_LOG_DEBUG,
"Format %s probed with size=%d and score=%d\n",
(*fmt)->name, probe_size, score);
#if 0
FILE *f = fopen("probestat.tmp", "ab");
fprintf(f, "probe_size:%d format:%s score:%d filename:%s\n", probe_size, (*fmt)->name, score, filename);
fclose(f);
#endif
}
}
if (!*fmt)
ret = AVERROR_INVALIDDATA;
fail:
/* Rewind. Reuse probe buffer to avoid seeking. */
ret2 = ffio_rewind_with_probe_data(pb, &buf, buf_offset);
if (ret >= 0)
ret = ret2;
av_freep(&pd.mime_type);
return ret < 0 ? ret : score;
}
int av_probe_input_buffer(AVIOContext *pb, const AVInputFormat **fmt,
const char *filename, void *logctx,
unsigned int offset, unsigned int max_probe_size)
{
int ret = av_probe_input_buffer2(pb, fmt, filename, logctx, offset, max_probe_size);
return ret < 0 ? ret : 0;
}