自定义AVIOContext的未定义AVFormatContext持续时间

Question

问题是为什么

后字段AVFormatContext :: duration未定义

avformat_open_input
avformat_find_stream_info

如果使用here或here中的自定义AVIOContext。

通过简单的文件打开，可以设置此字段。 Example

Answer 1

问题是我没有定义搜索功能，所以对于std :: istream这个例子应该是

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在eof

的情况下，你还应该在readFunction中添加clear for clear for clear