scrcpy/app/src/frames.c

107 lines
2.8 KiB
C
Raw Normal View History

#include "frames.h"
#include <SDL2/SDL_assert.h>
#include <SDL2/SDL_log.h>
#include <SDL2/SDL_mutex.h>
#include <libavutil/avutil.h>
#include <libavformat/avformat.h>
#include "config.h"
#include "lockutil.h"
SDL_bool frames_init(struct frames *frames) {
if (!(frames->decoding_frame = av_frame_alloc())) {
goto error_0;
}
if (!(frames->rendering_frame = av_frame_alloc())) {
goto error_1;
}
if (!(frames->mutex = SDL_CreateMutex())) {
goto error_2;
}
#ifndef SKIP_FRAMES
if (!(frames->rendering_frame_consumed_cond = SDL_CreateCond())) {
SDL_DestroyMutex(frames->mutex);
goto error_2;
}
frames->stopped = SDL_FALSE;
#endif
// there is initially no rendering frame, so consider it has already been
// consumed
frames->rendering_frame_consumed = SDL_TRUE;
return SDL_TRUE;
error_2:
av_frame_free(&frames->rendering_frame);
error_1:
av_frame_free(&frames->decoding_frame);
error_0:
return SDL_FALSE;
}
void frames_destroy(struct frames *frames) {
#ifndef SKIP_FRAMES
SDL_DestroyCond(frames->rendering_frame_consumed_cond);
#endif
SDL_DestroyMutex(frames->mutex);
av_frame_free(&frames->rendering_frame);
av_frame_free(&frames->decoding_frame);
}
static void frames_swap(struct frames *frames) {
AVFrame *tmp = frames->decoding_frame;
frames->decoding_frame = frames->rendering_frame;
frames->rendering_frame = tmp;
}
SDL_bool frames_offer_decoded_frame(struct frames *frames) {
mutex_lock(frames->mutex);
#ifndef SKIP_FRAMES
// if SKIP_FRAMES is disabled, then the decoder must wait for the current
// frame to be consumed
while (!frames->rendering_frame_consumed && !frames->stopped) {
cond_wait(frames->rendering_frame_consumed_cond, frames->mutex);
}
#else
if (!frames->rendering_frame_consumed) {
SDL_LogDebug(SDL_LOG_CATEGORY_APPLICATION, "Skip frame");
}
#endif
frames_swap(frames);
SDL_bool previous_frame_consumed = frames->rendering_frame_consumed;
frames->rendering_frame_consumed = SDL_FALSE;
mutex_unlock(frames->mutex);
return previous_frame_consumed;
}
const AVFrame *frames_consume_rendered_frame(struct frames *frames) {
SDL_assert(!frames->rendering_frame_consumed);
frames->rendering_frame_consumed = SDL_TRUE;
#ifndef SKIP_FRAMES
// if SKIP_FRAMES is disabled, then notify the decoder the current frame is
// consumed, so that it may push a new one
cond_signal(frames->rendering_frame_consumed_cond);
#endif
return frames->rendering_frame;
}
void frames_stop(struct frames *frames) {
#ifdef SKIP_FRAMES
(void) frames; // unused
#else
mutex_lock(frames->mutex);
frames->stopped = SDL_TRUE;
mutex_unlock(frames->mutex);
// wake up blocking wait
cond_signal(frames->rendering_frame_consumed_cond);
#endif
}