问题描述
我已经检查了此 http://www. 7twenty7.com/blog/2010/11/video-processing-with-av-foundation 逐帧获取视频.但是我真正的要求是在特定时间获得框架.我知道AVAssetReader应该有可能，我想知道AVAssetReader中是否有任何直接方法可以做到这一点.请提供有关如何在特定时间获得帧的任何指导.
I have checked this http://www.7twenty7.com/blog/2010/11/video-processing-with-av-foundation to get a video frame by frame. But my real requirement is to get a frame at particular time. I know that it should be possible by AVAssetReader, I wonder is there any direct method for this in AVAssetReader. Please give any guidance on how can I get frame at particular time.
我检查了AVAssetImageGenerator，但这不是我真正想要的.
I checked the AVAssetImageGenerator but this is not the thing I really wanted.
最后我找到了答案，您必须使用timeRange属性.那是唯一的方法.
Finally I found the answer, you have to use timeRange property. Thats the only way for this.
推荐答案
最后，我得到了答案.我在这里发布我的解决方案，希望对您有所帮助.
Finally I got an answer for this. I am posting my solution here, hope it helps some one.
使用AVAssetReader timeRange属性选择任何时间范围内的帧.如果要查找特定的帧，只需提供相同的开始时间和结束时间即可.
Use AVAssetReader timeRange property for selecting frames in any time range.If you are looking for particular frame just provide start and end time as same.
您需要记住两件事:
1.一旦调用AVAssetReader startReading方法，就无法重置timeRange.
1.once you call AVAssetReader startReading method you cannot reset timeRange.
2.您必须为此重新创建AVAssetReader，使用stopReading方法也确实无济于事.
2.You have to recreate AVAssetReader for this, using stopReading method also really won't help.
此链接可能也非常有用，我发现所有这些都非常有帮助:)如何使用avassetreader在音轨中进行搜索?
This link might be also really useful, I found all these very helpful:)How to seek within an audio track using avassetreader?
这篇关于使用AVAssetReader按时间值获取特定帧的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！