Linphone_call_take_video_snapshot saved empty file

Question

Linphone_call_take_video_snapshot saved empty file

I am working on a project based on Linphone-iPhone , the project requires a snapshot of the current video stream (both inside and outside).

I found this "linphone_call_take_video_snapshot" in liblinphone and gave it a try. The code was simple and worked without errors, but the size of the saved file is always 0 kb !

Here is the code:

- (void)capture {
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *file_path = [documentsDirectory stringByAppendingPathComponent:@"snapshot.jpeg"];
    LinphoneCall *call = linphone_core_get_current_call([LinphoneManager getLc]);
    const char *c_file_path = [file_path cStringUsingEncoding:NSUTF8StringEncoding];
    int ret = linphone_call_take_video_snapshot(call, c_file_path);

    if (ret >= 0 && [[NSFileManager defaultManager] fileExistsAtPath:file_path]) {
        UIImageWriteToSavedPhotosAlbum([UIImage imageWithContentsOfFile:file_path], nil,nil,nil);
    }
}