I am using libvlc 3.0.0 (I also tried 2.2.0) to capture frames from an mp4 file encoded by h264 (does not include sound, only video frames) on Windows 7 with Visual Studio 2012. I can play, pause, stop and search forward without any problems. But when I try to look back, I have problems:
Scenario: if I only call libvlc_media_player_set_position (or libvlc_media_player_set_time ), it looks like it is moving to a position. But vlc stops sending received callbacks (in other words, the player freezes) until it reaches the same (or next) frame before calling the libvlc_media_player_set_position function.
counter = 0; while (true) { sleep(40); // 25 hz ++counter; if(counter % 100 = 0) { // assuming current_position > 0.1f libvlc_media_player_set_position(p_mi, 0.1f); } }
Scenario: I can make it work only if I first stopped the player and then started playing from the very beginning.
counter = 0; while (true) { sleep(40); // 25 hz ++counter; if(counter % 100 = 0) { // assuming current_position > 0.1f libvlc_media_player_stop(p_mi); libvlc_media_player_play(p_mi); libvlc_media_player_set_position(p_mi, 0.1f); } }
The problem with this scenario is that if I go back a bit, I get an error (vlc prints an error on the command line) core decoder error: cannot continue streaming due to errors . After this error, it stops playing (it freezes again), and the next time I try to find, I get an "Access Violation" error: Unhandled exception at 0x... (libavcodec_plugin.dll) in vlctest.exe: 0xC0000005: Access violation reading location 0x00000040
It is not correct to restart the video for the search first. Did I miss something?
Thanks in advance!
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