dynamically increase probe buffer until format is detected

Originally committed as revision 4920 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2006-02-02 11:27:35 +00:00
parent 7d453f4500
commit a877eedce5
1 changed files with 14 additions and 13 deletions

View File

@ -508,7 +508,8 @@ int av_open_input_stream(AVFormatContext **ic_ptr,
}
/** Size of probe buffer, for guessing file type from file contents. */
#define PROBE_BUF_SIZE 2048
#define PROBE_BUF_MIN 2048
#define PROBE_BUF_MAX 131072
/**
* Open a media file as input. The codec are not opened. Only the file
@ -526,8 +527,7 @@ int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
int buf_size,
AVFormatParameters *ap)
{
int err, must_open_file, file_opened;
uint8_t buf[PROBE_BUF_SIZE];
int err, must_open_file, file_opened, probe_size;
AVProbeData probe_data, *pd = &probe_data;
ByteIOContext pb1, *pb = &pb1;
@ -535,7 +535,7 @@ int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
pd->filename = "";
if (filename)
pd->filename = filename;
pd->buf = buf;
pd->buf = NULL;
pd->buf_size = 0;
if (!fmt) {
@ -561,9 +561,11 @@ int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
if (buf_size > 0) {
url_setbufsize(pb, buf_size);
}
if (!fmt) {
for(probe_size= PROBE_BUF_MIN; probe_size<=PROBE_BUF_MAX && !fmt; probe_size<<=1){
/* read probe data */
pd->buf_size = get_buffer(pb, buf, PROBE_BUF_SIZE);
pd->buf= av_realloc(pd->buf, probe_size);
pd->buf_size = get_buffer(pb, pd->buf, probe_size);
if (url_fseek(pb, 0, SEEK_SET) == (offset_t)-EPIPE) {
url_fclose(pb);
if (url_fopen(pb, filename, URL_RDONLY) < 0) {
@ -571,13 +573,11 @@ int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
goto fail;
}
}
}
}
/* guess file format */
if (!fmt) {
fmt = av_probe_input_format(pd, 1);
}
av_freep(&pd->buf);
}
/* if still no format found, error */
if (!fmt) {
@ -606,6 +606,7 @@ int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
goto fail;
return 0;
fail:
av_freep(&pd->buf);
if (file_opened)
url_fclose(pb);
*ic_ptr = NULL;
@ -3223,7 +3224,7 @@ int av_read_image(ByteIOContext *pb, const char *filename,
AVImageFormat *fmt,
int (*alloc_cb)(void *, AVImageInfo *info), void *opaque)
{
uint8_t buf[PROBE_BUF_SIZE];
uint8_t buf[PROBE_BUF_MIN];
AVProbeData probe_data, *pd = &probe_data;
offset_t pos;
int ret;
@ -3232,7 +3233,7 @@ int av_read_image(ByteIOContext *pb, const char *filename,
pd->filename = filename;
pd->buf = buf;
pos = url_ftell(pb);
pd->buf_size = get_buffer(pb, buf, PROBE_BUF_SIZE);
pd->buf_size = get_buffer(pb, buf, PROBE_BUF_MIN);
url_fseek(pb, pos, SEEK_SET);
fmt = av_probe_image_format(pd);
}