From e253a9e2b3d683eb51db7c776326eb07de10ad4c Mon Sep 17 00:00:00 2001 From: Luca Barbato Date: Thu, 13 Mar 2014 19:54:00 +0100 Subject: avformat: Move av_probe_input* to format.c --- libavformat/format.c | 139 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 138 insertions(+), 1 deletion(-) (limited to 'libavformat/format.c') diff --git a/libavformat/format.c b/libavformat/format.c index 7e9ca33a52..073f770942 100644 --- a/libavformat/format.c +++ b/libavformat/format.c @@ -19,9 +19,12 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ +#include "libavutil/avstring.h" + +#include "avio_internal.h" #include "avformat.h" +#include "id3v2.h" #include "internal.h" -#include "libavutil/avstring.h" /** * @file @@ -181,3 +184,137 @@ AVInputFormat *av_find_input_format(const char *short_name) return fmt; return NULL; } + +AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, + int *score_max) +{ + AVProbeData lpd = *pd; + AVInputFormat *fmt1 = NULL, *fmt; + int score, id3 = 0; + + 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) { + lpd.buf += id3len; + lpd.buf_size -= id3len; + } + id3 = 1; + } + + fmt = NULL; + while ((fmt1 = av_iformat_next(fmt1))) { + if (!is_opened == !(fmt1->flags & AVFMT_NOFILE)) + continue; + score = 0; + if (fmt1->read_probe) { + score = fmt1->read_probe(&lpd); + } else if (fmt1->extensions) { + if (av_match_ext(lpd.filename, fmt1->extensions)) + score = AVPROBE_SCORE_EXTENSION; + } + if (score > *score_max) { + *score_max = score; + fmt = fmt1; + } else if (score == *score_max) + fmt = NULL; + } + + // A hack for files with huge id3v2 tags -- try to guess by file extension. + if (!fmt && is_opened && *score_max < AVPROBE_SCORE_EXTENSION / 2) { + while ((fmt = av_iformat_next(fmt))) + if (fmt->extensions && + av_match_ext(lpd.filename, fmt->extensions)) { + *score_max = AVPROBE_SCORE_EXTENSION / 2; + break; + } + } + + if (!fmt && id3 && *score_max < AVPROBE_SCORE_EXTENSION / 2 - 1) { + while ((fmt = av_iformat_next(fmt))) + if (fmt->extensions && av_match_ext("mp3", fmt->extensions)) { + *score_max = AVPROBE_SCORE_EXTENSION / 2 - 1; + break; + } + } + + return fmt; +} + +AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened) +{ + int score = 0; + return av_probe_input_format2(pd, is_opened, &score); +} + +/* size of probe buffer, for guessing file type from file contents */ +#define PROBE_BUF_MIN 2048 +#define PROBE_BUF_MAX (1 << 20) + +int av_probe_input_buffer(AVIOContext *pb, 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; + + if (!max_probe_size) + max_probe_size = PROBE_BUF_MAX; + else if (max_probe_size > PROBE_BUF_MAX) + max_probe_size = PROBE_BUF_MAX; + else if (max_probe_size < PROBE_BUF_MIN) + return AVERROR(EINVAL); + + if (offset >= max_probe_size) + return AVERROR(EINVAL); + avio_skip(pb, offset); + max_probe_size -= offset; + + for (probe_size = PROBE_BUF_MIN; probe_size <= max_probe_size && !*fmt; + probe_size = FFMIN(probe_size << 1, + FFMAX(max_probe_size, probe_size + 1))) { + int score = probe_size < max_probe_size ? AVPROBE_SCORE_MAX / 4 : 0; + + /* Read probe data. */ + if ((ret = av_reallocp(&buf, probe_size + AVPROBE_PADDING_SIZE)) < 0) + return ret; + if ((ret = avio_read(pb, buf + pd.buf_size, + probe_size - pd.buf_size)) < 0) { + /* Fail if error was not end of file, otherwise, lower score. */ + if (ret != AVERROR_EOF) { + av_free(buf); + return ret; + } + score = 0; + ret = 0; /* error was end of file, nothing read */ + } + pd.buf_size += ret; + pd.buf = buf; + + 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_MAX / 4) { + av_log(logctx, AV_LOG_WARNING, + "Format detected only with low score of %d, " + "misdetection possible!\n", score); + } else + av_log(logctx, AV_LOG_DEBUG, + "Probed with size=%d and score=%d\n", probe_size, score); + } + } + + if (!*fmt) { + av_free(buf); + return AVERROR_INVALIDDATA; + } + + /* Rewind. Reuse probe buffer to avoid seeking. */ + if ((ret = ffio_rewind_with_probe_data(pb, buf, pd.buf_size)) < 0) + av_free(buf); + + return ret; +} -- cgit v1.2.3