Question

提前谢谢。我正在尝试在Texas Instrument制作的beaglebone black（BBB）上播放视频。由于有很多关于使用ffmpeg和SDL的好教程，我决定使用它。获取有关视频和编解码器的信息，使用ffmpeg解码帧。显示使用SDL监控的解码帧。

我正在使用SDL2，它使用渲染器，纹理来显示图像到屏幕。根据SDL wiki，渲染器使用GPU加速。但这是一个问题。视频播放得太慢......约0.5fps？

所以我转向使用软件渲染的SDL1.2。它通过CPU RAM显示yuv overlay。

我认为可能BBB不支持GPU加速并且谷歌搜索但是无法得到答案。有什么帮助吗？这是我使用SDL2的代码。

 #include <libavutil/frame.h>
 #include <libavutil/avutil.h>
 #include <libavcodec/avcodec.h>
 #include <libavformat/avformat.h>
 #include <libswscale/swscale.h>

 #include <SDL2/SDL.h>
 #include <SDL2/SDL_thread.h>

 #ifdef __MINGW32__
 #undef main /* Prevents SDL from overriding main() */
 #endif

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/fb.h>
#include <errno.h>

int main(int argc, char *argv[]) {

AVFormatContext *pFormatCtx = NULL;
int             i, videoStream;
AVCodecContext  *pCodecCtx = NULL;
AVCodec         *pCodec = NULL;
AVFrame         *pFrame = NULL;
AVPacket        packet;
int             frameFinished;

SDL_Window    *window=NULL;
SDL_Renderer    *renderer=NULL;
SDL_Texture     *bmp=NULL;
SDL_Event       event;

int fbfd, ret;
struct fb_var_screeninfo fbvar;

if(argc < 2) {
  fprintf(stderr, "Usage: test <file>\n");
  exit(1);
}
// Register all formats and codecs
av_register_all();

if(SDL_Init(SDL_INIT_VIDEO)) {
fprintf(stderr, "Could not initialize SDL - %s\n", SDL_GetError());
exit(1);
}

// Open video file
if(avformat_open_input(&pFormatCtx, argv[1], NULL, NULL)!=0)
return -1; // Couldn't open file

// Retrieve stream information
if(avformat_find_stream_info(pFormatCtx, NULL)<0)
return -1; // Couldn't find stream information

// Dump information about file onto standard error
av_dump_format(pFormatCtx, 0, argv[1], 0);

// Find the first video stream
videoStream=-1;
for(i=0; i<pFormatCtx->nb_streams; i++)
  if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO) {
  videoStream=i;
  break;
}
if(videoStream==-1)
return -1; // Didn't find a video stream

// Get a pointer to the codec context for the video stream
pCodecCtx=pFormatCtx->streams[videoStream]->codec;
// Find the decoder for the video stream
pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
if(pCodec==NULL) {
fprintf(stderr, "Unsupported codec!\n");
return -1; // Codec not found
}


// Open codec
if( avcodec_open2(pCodecCtx, pCodec, NULL)<0 )
return -1; // Could not open codec

// Allocate video frame
pFrame=av_frame_alloc();


int ctxW= pCodecCtx->width;
int ctxH= pCodecCtx->height;

 window =
  SDL_CreateWindow("test",
    SDL_WINDOWPOS_UNDEFINED,SDL_WINDOWPOS_UNDEFINED, 0, 0,
    SDL_WINDOW_BORDERLESS  SDL_WINDOW_FULLSCREEN_DESKTOP);

 renderer = SDL_CreateRenderer(window, -1, 0);

 // Allocate a place to put our YUV image on that screen
 bmp = SDL_CreateTexture(renderer, 
        SDL_PIXELFORMAT_YV12, SDL_TEXTUREACCESS_STREAMING, 
        pCodecCtx->width, pCodecCtx->height);

 av_init_packet(&packet);

 // Read frames and save first five frames to disk
 while(av_read_frame(pFormatCtx, &packet)>=0) {
  // Is this a packet from the video stream?
   if(packet.stream_index==videoStream) {
  // Decode video frame
    avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);

  // Did we get a video frame?
     if(frameFinished) {
       SDL_UpdateYUVTexture(bmp, NULL, pFrame->data[0], pFrame->linesize[0],
        pFrame->data[1], pFrame->linesize[1],
        pFrame->data[2], pFrame->linesize[2]);
      }

      SDL_RenderClear(renderer);
      SDL_RenderCopy(renderer, bmp, NULL, NULL);
      SDL_RenderPresent(renderer);
   }
  SDL_Delay(15);


SDL_PollEvent(&event);
switch(event.type) {
case SDL_QUIT:
  SDL_Quit();
  exit(0);
  break;
default:
  break;
}


}

// Free the packet that was allocated by av_read_frame
 av_free_packet(&packet);

// Free the YUV frame
av_frame_free(&pFrame);

// Close the codec
avcodec_close(pCodecCtx);

// Close the video file
avformat_close_input(&pFormatCtx);

return 0;
}

Answer 1

是的beaglebone black确实支持gpu硬件加速，

来自此维基百科链接https://en.wikipedia.org/wiki/BeagleBoard

BBB拥有 PowerVR SGX530 GPU，其详细信息可在此处找到https://en.wikipedia.org/wiki/PowerVR#Series_5

来自BBB官方网站http://beagleboard.org/BLACK

处理器：AM335x1GHzARM®Cortex-A8

512MB DDR3 RAM

4GB 8位eMMC板载闪存

3D图形加速器

NEON浮点加速器

2x PRU 32位微控制器

您也可以查看 REF： BBONEBLK_SRM BeagleBone黑色系统参考手册 Rev A5.2

beaglebone black支持gpu硬件加速吗？

1 个答案: