ffmpeg部分机器上有花屏的问题
原代码例如以下:
while(av_read_frame(formatCtx, &packet)>=0 && !_stop && NULL!=window && bInit) { // Is this a packet from the video stream? if(packet.stream_index==videoStream) { // Decode video frame avcodec_decode_video2(codecCtx, decodedFrame, &frameFinished, &packet); // Did we get a video frame? if(frameFinished) { // Convert the image from its native format to RGBA sws_scale ( sws_ctx, (uint8_t const * const *)decodedFrame->data, decodedFrame->linesize, 0, codecCtx->height, frameRGBA->data, frameRGBA->linesize ); if(packet.dts == AV_NOPTS_VALUE && decodedFrame->opaque && *(uint64_t*)decodedFrame->opaque != AV_NOPTS_VALUE) { pts = *(uint64_t *)decodedFrame->opaque; LOGD("pst1: %d",pts); } else if(packet.dts != AV_NOPTS_VALUE) { pts = packet.dts; LOGD("pst2: %d",pts); } else { pts = 0; LOGD("pst3: %d",pts); } //pts = av_q2d(codecCtx->time_base) * 1000000.0 * i * 2; pts *= 1000; //LOGD("debug %d,%d,%f",pts, (long)(av_q2d(codecCtx->time_base) * 1000000.0 * i * 2), av_q2d(codecCtx->time_base)); if(0 == pts || 0 == baseTime) { baseTime = av_gettime() - pts; LOGD("BASETIME: %d",baseTime); }else{ waitTime = (baseTime + pts) - av_gettime(); LOGD("WAITTIME: %d, %d",waitTime,pts); } //waitTime = (av_q2d(codecCtx->time_base) * 1000.0 - 0.0) * 1000; if(waitTime>0) usleep(waitTime); if(!_stop) { synchronized(lockWindow) { if(!_stop && NULL!=window) { // lock the window buffer if (ANativeWindow_lock(pWin, &windowBuffer, NULL) < 0) { LOGE("cannot lock window"); } else { // draw the frame on buffer //LOGD("copy buffer %d:%d:%d", width, height, width*height*RGB_SIZE); //LOGD("window buffer: %d:%d:%d", windowBuffer.width, windowBuffer.height, windowBuffer.stride); memcpy(windowBuffer.bits, buffer, width * height * RGB_SIZE); // unlock the window buffer and post it to display ANativeWindow_unlockAndPost(pWin); // count number of frames ++i; } } } } } }细致分析后发现 部分分辨率又可以正常展示,感觉是宽度错位导致的,分析例如以下: ORG: 176 * 144 F
X2: 352 288 O X3: 528 432 F X4: 704 576 O X6: 1056 * O X1.1 193 158 F X1.2 211 172 F X1.5 264 216 F X0.5 88 72 F X2?: 352 290 O
X2?: 352 600 O X2?: 352 720 O X4?: 704 720 O X6?: 1056 720 O 1280 ---1312 105611841248 ok发现分辨率依照%64+32对齐, 感觉是内存对齐造成的, 查看ANativeWindow_Buffer例如以下
typedef struct ANativeWindow_Buffer { // The number of pixels that are show horizontally. int32_t width; // The number of pixels that are shown vertically. int32_t height; // The number of *pixels* that a line in the buffer takes in // memory. This may be >= width. int32_t stride; // The format of the buffer. One of WINDOW_FORMAT_* int32_t format; // The actual bits. void* bits; // Do not touch. uint32_t reserved[6];} ANativeWindow_Buffer; 输出stride和width的日志发现,假设正常显示则stride==width, 通过凝视能够看出应该是内存对齐问题导致的,调整代码:
if(packet.stream_index==videoStream) { // Decode video frame avcodec_decode_video2(codecCtx, decodedFrame, &frameFinished, &packet); // Did we get a video frame? if(frameFinished) { // Convert the image from its native format to RGBA sws_scale ( sws_ctx, (uint8_t const * const *)decodedFrame->data, decodedFrame->linesize, 0, codecCtx->height, frameRGBA->data, frameRGBA->linesize ); if(packet.dts == AV_NOPTS_VALUE && decodedFrame->opaque && *(uint64_t*)decodedFrame->opaque != AV_NOPTS_VALUE) { pts = *(uint64_t *)decodedFrame->opaque; LOGD("pst1: %d",pts); } else if(packet.dts != AV_NOPTS_VALUE) { pts = packet.dts; LOGD("pst2: %d",pts); } else { pts = 0; LOGD("pst3: %d",pts); } //pts = av_q2d(codecCtx->time_base) * 1000000.0 * i * 2; pts *= 1000; //LOGD("debug %d,%d,%f",pts, (long)(av_q2d(codecCtx->time_base) * 1000000.0 * i * 2), av_q2d(codecCtx->time_base)); if(0 == pts || 0 == baseTime) { baseTime = av_gettime() - pts; LOGD("BASETIME: %d",baseTime); }else{ waitTime = (baseTime + pts) - av_gettime(); LOGD("WAITTIME: %d, %d",waitTime,pts); } //waitTime = (av_q2d(codecCtx->time_base) * 1000.0 - 0.0) * 1000; if(waitTime>0) usleep(waitTime); if(!_stop) { synchronized(lockWindow) { if(!_stop && NULL!=window) { // lock the window buffer if (ANativeWindow_lock(pWin, &windowBuffer, NULL) < 0) { LOGE("cannot lock window"); } else { // draw the frame on buffer //LOGD("copy buffer %d:%d:%d", width, height, width*height*RGB_SIZE); //LOGD("window buffer: %d:%d:%d", windowBuffer.width, windowBuffer.height, windowBuffer.stride); //memcpy(windowBuffer.bits, buffer, width * height * RGB_SIZE); if(windowBuffer.width >= windowBuffer.stride){ memcpy(windowBuffer.bits, buffer, width * height * RGB_SIZE); }else{ //skip stride-width 跳过padding部分内存 for(int i=0;i<height;++i) memcpy(windowBuffer.bits + windowBuffer.stride * i * RGB_SIZE , buffer + width * i * RGB_SIZE , width * RGB_SIZE); } // unlock the window buffer and post it to display ANativeWindow_unlockAndPost(pWin); // count number of frames ++i; } } } } } }
通过行拷贝方式,跳过后面对齐部分的内存,解决这个问题,
