FFMPEG sws_scale在Android上崩溃

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我有一个应用程序将图像转换为视频,在Google Play中我看到以下崩溃(我得到的唯一细节是函数名称,我不理解其余的):

backtrace:
#00 pc 0000cc78 /data/app-lib/com.myapp-1/libswscale.so (sws_scale+204)
#01 pc 000012af /data/app-lib/com.myapp-1/libffmpeg.so (OpenImage+322)

code around pc:
79065c58 e58d8068 e58d2070 e58d3074 059d00b0 

代码指向函数sws_scale,代码几乎一直在我的设备上工作(Nexus 5)但我看到很多报告,即使是同一个设备也有这个问题.知道为什么会这样吗?

AVFrame* OpenImage(const char* imageFileName,int W_VIDEO,int H_VIDEO,int* numBytes)
{
    AVFormatContext *pFormatCtx;
    AVCodecContext *pCodecCtx;
    AVCodec *pCodec;
    AVFrame *pFrame;
    int frameFinished;
    uint8_t *buffer;
    AVPacket packet;
    int srcBytes;

    AVFrame* frame2 = NULL;// scaled frame
    uint8_t* frame2_buffer;
    struct SwsContext *resize;

    if(av_open_input_file(&pFormatCtx,imageFileName,NULL,NULL)!=0)
    {
        LOGI("Can't open image file '%s'\n",imageFileName);
        return NULL;
    }
    //dump_format(pFormatCtx,0);
    if (av_find_stream_info(pFormatCtx) < 0)
    {
        LOGI("Can't find stream info.");
        return NULL;
    }
    pCodecCtx = pFormatCtx->streams[0]->codec;
    pCodecCtx->pix_fmt = PIX_FMT_YUV420P;

    // Find the decoder for the video stream
    pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
    if (!pCodec)
    {
        LOGI("Codec not found\n");
        return NULL;
    }

    // Open codec
    if(avcodec_open(pCodecCtx,pCodec)<0)
    {
        LOGI("Could not open codec\n");
        return NULL;
    }
    pFrame = avcodec_alloc_frame();
    if (!pFrame)
    {
        LOGI("Can't allocate memory for AVFrame\n");
        return NULL;
    }

    // Determine required buffer size and allocate buffer
    srcBytes = avpicture_get_size(PIX_FMT_YUV420P,pCodecCtx->width,pCodecCtx->height);
    buffer = (uint8_t *) av_malloc(srcBytes * sizeof(uint8_t));
    avpicture_fill((AVPicture *) pFrame,buffer,PIX_FMT_YUV420P,pCodecCtx->height);

    // Read frame
    if (av_read_frame(pFormatCtx,&packet) >= 0)
    {
        int ret;
//      if(packet.stream_index != 0)
//          continue;
        ret = avcodec_decode_video2(pCodecCtx,pFrame,&frameFinished,&packet);
        if (ret > 0)
        {
            //LOGI("Frame is decoded,size %d\n",ret);
            pFrame->quality = 4;

            // Create another frame for resized result
            frame2 = avcodec_alloc_frame();
            *numBytes = avpicture_get_size(PIX_FMT_YUV420P,W_VIDEO,H_VIDEO);
            frame2_buffer = (uint8_t *)av_malloc(*numBytes * sizeof(uint8_t));
            avpicture_fill((AVPicture*)frame2,frame2_buffer,H_VIDEO);

            // Get resize context
            resize = sws_getContext(pCodecCtx->width,pCodecCtx->height,H_VIDEO,SWS_BICUBIC,NULL);

            // frame2 should be filled with resized samples
            ret = sws_scale(resize,(const uint8_t* const*)pFrame->data,pFrame->linesize,frame2->data,frame2->linesize);
            sws_freeContext(resize);
        }
        else
            LOGI("Error [%d] while decoding frame: %s\n",ret,strerror(AVERROR(ret)));
    }
    av_free(pFrame);
    av_free_packet(&packet);
    avcodec_close(pCodecCtx);
    //av_free(pCodecCtx);
    av_close_input_file(pFormatCtx);
    return frame2;
}
最佳答案
在你的avcodec_decode_video2之后,不要只检查ret.你也需要检查frameFinished.如果frameFinished == 0,则不应使用您的框架(因为未填充).我不知道图像,但是当你解码视频时,它经常发生.您需要读取下一个数据包并进行下一次avcodec_decode_video2调用.

旁注:你为什么强迫pCodecCtx-> pix_fmt = PIX_FMT_YUV420P?它由av_find_stream_info自动设置为正确的格式,您应该将其用作sws_getContext参数.

最后一件事:无需用avpicture_fill填充你的pFrame.你只需要av_frame_alloc()它,avcodec_decode_video2将负责填充它.

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