Recherche avancée

Sur d’autres sites (9276)

• Building FFmpeg for android to run command line args

  11 septembre 2012, par Zargoon

  I am trying to build the FFmpeg library to use in my android app with the NDK. The reason for this is because I am using the native video capture feature in android because I really don't want to write my own video recorder. However, the native video capture only allows for either high-quality encoding, or low quality encoding. I want something in between, and I believe that the solution is to use the FFmpeg library to re-encode the high quality video to be lighter.

  So far I have been able to build the FFmpeg library according to this guide : http://www.roman10.net/how-to-build-ffmpeg-for-android/ and which a few tweaks I have been able to get it to work.

  However, everything that I've found seems to be about writing your own encoder, which seems like overkill to me. All that I really want to do is send a string in command line format to the main() function of FFmpeg and re-encode my video. However, I can't seem to figure out how I build FFmpeg to give me access to the main method. I found this post : Compile ffmpeg.c and call its main() via JNI which links to a project doing what I want more of less, but for the life of me I cannot figure out what is going on. It also seems like he is compiling more than I want, and I would really like to keep my application as light weight as possible.

  Some additional direction would be extremely helpful. Thank you.

• Building FFmpeg for Android to use command line arguments

  28 juin 2013, par Zargoon

  I am trying to build the FFmpeg library to use in my android app with the NDK. The reason for this is because I am using the native video capture feature in android because I really don't want to write my own video recorder. However, the native video capture only allows for either high-quality encoding, or low quality encoding. I want something in between, and I believe that the solution is to use the FFmpeg library to re-encode the high quality video to be lighter.

  So far I have been able to build the FFmpeg library according to this guide : http://www.roman10.net/how-to-build-ffmpeg-for-android/ and which a few tweaks I have been able to get it to work.

  However, everything that I've found seems to be about writing your own encoder, which seems like overkill to me. All that I really want to do is send a string in command line format to the main() function of FFmpeg and re-encode my video. However, I can't seem to figure out how I build FFmpeg to give me access to the main method. I found this post : Compile ffmpeg.c and call its main() via JNI which links to a project doing what I want more of less, but for the life of me I cannot figure out what is going on. It also seems like he is compiling more than I want, and I would really like to keep my application as light weight as possible.

  Some additional direction would be extremely helpful. Thank you.

• ffmpeg output video is not up to the par

  4 juin 2015, par user3668629

  I am trying to overlay text on video with ffmpeg. The following command is working fine. My concern is the resultant video quality. There is a difference in quality between the original and output video. With the following command, the output video size is almost half of the original one. How can I maintain the size in the output vid ? Any suggestions. I have tried to increase the framerate as well as bitrate, but the quality does not improve. Can you please give me suggestions of how can I retain the same video quality and size in my output video. Your help will be much appreciated. Thank you.

  $ffmpeg -i input_video.mp4 -filter:v drawtext="fontfile=/path/to/font.ttf: text='Demo Text': fontcolor=white: fontsize=24" -video_size hd720 -codec:v mpeg4 output_video.mp4