ffplay---源码解析---even_loop-优快云博客

本文链接：https://blog.youkuaiyun.com/qq_42024067/article/details/107580748

本文详细解析ffplay中stream_seek函数的应用场景，包括播放结束后的重新开始、多文件切换、键盘快进快退操作以及鼠标移动触发的seek操作。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

/* handle an event sent by the GUI */
static void event_loop(VideoState *cur_stream)
{
   
    SDL_Event event;
    double incr, pos, frac;

    for (;;) {
   
        double x;
        refresh_loop_wait_event(cur_stream, &event);
        switch (event.type) {
   
        case SDL_KEYDOWN:									键盘事件
            if (exit_on_keydown || event.key.keysym.sym == SDLK_ESCAPE || event.key.keysym.sym == SDLK_q) {
   
                do_exit(cur_stream);
                break;
            }
            // If we don't yet have a window, skip all key events, because read_thread might still be initializing...
            if (!cur_stream->width)
                continue;
            switch (event.key.keysym.sym) {
   
            case SDLK_f:							按下按键f
                toggle_full_screen(cur_stream);
                cur_stream->force_refresh = 1;
                break;
            case SDLK_p:
            case SDLK_SPACE:						按下空格
                toggle_pause(cur_stream);
                break;
            case SDLK_m:
                toggle_mute(cur_stream);
                break;
            case SDLK_KP_MULTIPLY:
            case SDLK_0:
                update_volume(cur_stream, 1, SDL_VOLUME_STEP);
                break;
            case SDLK_KP_DIVIDE:
            case SDLK_9:
                update_volume(cur_stream, -1, SDL_VOLUME_STEP);
                break;
            case SDLK_s: // S: Step to next frame
                step_to_next_frame(cur_stream);
                break;
            case SDLK_a:
                stream_cycle_channel(cur_stream, AVMEDIA_TYPE_AUDIO);
                break;
            case SDLK_v:
                stream_cycle_channel(cur_stream, AVMEDIA_TYPE_VIDEO);
                break;
            case SDLK_c:
                stream_cycle_channel(cur_stream, AVMEDIA_TYPE_VIDEO);
                stream_cycle_channel(cur_stream, AVMEDIA_TYPE_AUDIO);
                stream_cycle_channel(cur_stream, AVMEDIA_TYPE_SUBTITLE);
                break;
            case SDLK_t:
                stream_cycle_channel(cur_stream, AVMEDIA_TYPE_SUBTITLE);
                break;
            case SDLK_w:
#if CONFIG_AVFILTER									//滤镜
                if (cur_stream->show_mode == SHOW_MODE_VIDEO && cur_stream->vfilter_idx < nb_vfilters - 1) {
   
                    if (++cur_stream->vfilter_idx >= nb_vfilters)
                        cur_stream->vfilter_idx = 0;
                } else {
   
                    cur_stream->vfilter_idx = 0;
                    toggle_audio_display(cur_stream);
                }
#else
                toggle_audio_display(cur_stream);
#endif
                break;
            case SDLK_PAGEUP:
                if (cur_stream->ic->nb_chapters <= 1) {
   		如果只有一个视频则向前/向后10分钟
                    incr = 600.0;
                    goto do_seek;
                }
                seek_chapter(cur_stream