int av_probe_input_buffer2(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; uint8_t *mime_type; int ret = 0, probe_size, buf_offset = 0; int score = 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); #ifdef FF_API_PROBE_MIME if (pb->av_class) av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &pd.mime_type); #endif #if !FF_API_PROBE_MIME if (!*fmt && pb->av_class && av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type) >= 0 && mime_type) { if (!av_strcasecmp(mime_type, "audio/aacp")) { *fmt = av_find_input_format("aac"); } av_freep(&mime_type); } #endif 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))) { 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 */ } 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. */ if (ret >= 0) ret = ffio_rewind_with_probe_data(pb, &buf, buf_offset); #ifdef FF_API_PROBE_MIME av_free(pd.mime_type); #endif return ret < 0 ? ret : score; }