except sometimes it is twice what one would expect because of field rate versus frame rate.除以上三种时间基外，FFmpeg还有一个内部时间基AV_TIME_BASE以及分数形式的AV_TIME_BASE_Q。AV_TIME_BASE及AV_TIME_BASE_Q用于FFmpeg内部函数处理，使用此时间基计算得到的时间值表示的是微秒。转换时间值...
typedef struct URLProtocol { const char *name; int (*url_open)( URLContext *h, const char *url, int flags); /** * This callback is to be used by protocols which open further nested * protocols. options are then to be passed to ffurl_open()/ffurl_connect() * for those nested ...
[8].Graphviz典型例子 [9].https:///blog/what-is-low-latency/
* @note this function isn't guaranteed to open all the codecs, so * options being non-empty at return is a perfectly normal behavior. * * @todo Let the user decide somehow what information is needed so that * we do not waste time getting stuff the user does not need. */intavformat...
{ /* When using a constant Q-scale, don't mess with lambda */ break; } /* rate control stuff * allow between the nominal bitrate, and what psy's bit reservoir says to target * but drift towards the nominal bitrate always */ frame_bits = put_bits_count(&s->pb); rate_bits = ...
* that what is there are valid frames for the decoder. It will split what is * stored in the file into frames and return one for each call. It will not * omit invalid data between valid frames so as to give the decoder the maximum ...
(So what's up with those "truncated bitstreams"? Well, as we'll see in a moment, the data in a video stream is split up into packets. Since the amount of data per video frame can vary, the boundary between two video frames need not coincide with a packet boundary. Here, we're ...
We'll start with a quick lesson about what is video, audio, codec and container and then we'll go to a crash course on how to use FFmpeg command line and finally we'll write code, feel free to skip directly to the section Learn FFmpeg libav the Hard Way....
* @todo Let the user decide somehow what information is needed so that * we do not waste time getting stuff the user does not need. */intavformat_find_stream_info(AVFormatContext *ic, AVDictionary **options); 这个函数会读取一段视频文件数据并尝试解码,将取到的流信息填入 AVFormatContext.streams...
just return what is stored in the container#defineAVFMT_FLAG_NOPARSE0x0020///< Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames. Also seeking to frames can not work if parsing to find frame boundaries has been...