移植EMCV到DM6467(5)——修改encodedecode demo测试算法封装

1 修改encodedecode demo测试codec

接下来，我们需要将修改过后的videnc_copy集成到encodedecodedemo中，实现实时采集视频、使用EMCV添加矩形框、然后输出显示的功能。

1.1 修改demo

（1）修改encodedecode.cfg

要使用videnc_copy，需要在encodedecode.cfg中修改createFromServer函数的参数，如下所示。

var demoEngine = Engine.createFromServer( "encodedecode", "bin/ti_platforms_evmDM6467/all.x64P", "ti.sdo.ce.examples.servers.all_codecs" );

（2）修改codecs.c

由于我们不对视频进行H264编码，所以需要在codecs中注释掉相关的参数定义。

#if 0 /* Use extended dynamic parameters to allow tweaking of the QP value */ static IH264VENC_DynamicParams extDynParams = { { sizeof(IVIDENC1_DynamicParams), /* size */ 576, /* inputHeight */ 720, /* inputWidth */ 25000, /* refFrameRate */ 25000, /* targetFrameRate */ 2000000, /* targetBitRate (override in app) */ 30, /* intraFrameInterval */ XDM_DECODE_AU, /* generateHeader */ 0, /* captureWidth */ IVIDEO_NA_FRAME, /* forceFrame */ 1, /* interFrameInterval */ 0 /* mbDataFlag */ }, 18, /* QPISlice */ 20, /* QPSlice */ 51, /* RateCtrlQpMax */ 0, /* RateCtrlQpMin */ 0, /* NumRowsInSlice */ 0, /* LfDisableIdc */ 0, /* LFAlphaC0Offset */ 0, /* LFBetaOffset */ 0, /* ChromaQPOffset */ 0, /* SecChromaQPOffset */ }; #endif

（3）修改capture.c

由于encodedecode中默认是要将输入的YUV422视频流转换为YUV420再传递给video线程，而我们的videnc_copy是直接处理YUV422视频流，不需要进行转换，所以需要在Capture.c中修改部分代码。

#if 0 /* Configure color conversion job */ if (Ccv_config(hCcv, hInBuf, hDstBuf) < 0) { ERR("Failed to configure 422 to 420 color conversion job\n"); cleanup(THREAD_FAILURE); } else printf("Succeed to configure 422 to 420 color conversion job.\n"); #endif frameSkip = TRUE; /* Signal that initialization is done and wait for other threads */ Rendezvous_meet(envp->hRendezvousInit); while (!gblGetQuit()) { if (frameSkip) { /* Capture an extra frame to halve the frame rate */ if (Capture_get(hCapture, &hCapBuf) < 0) { ERR("Failed to get capture buffer\n"); cleanup(THREAD_FAILURE); } if (Capture_put(hCapture, hCapBuf) < 0) { ERR("Failed to put capture buffer\n"); cleanup(THREAD_FAILURE); } } /* Get a buffer from the capture driver to encode */ if (Capture_get(hCapture, &hCapBuf) < 0) { ERR("Failed to get capture buffer\n"); cleanup(THREAD_FAILURE); } if (resize) { /* Resize buffer from 720P to a smaller resolution */ if (Resize_execute(hRsz, hCapBuf, hIntBuf) < 0) { ERR("Failed to execute resize job\n"); cleanup(THREAD_FAILURE); } hInBuf = hIntBuf; } else { hInBuf = hCapBuf; } //if (Ccv_execute(hCcv, hInBuf, hDstBuf) < 0) { // ERR("Failed to execute color conversion job\n"); // cleanup(THREAD_FAILURE); //} /* Send color converted buffer to video thread for encoding */ if (Fifo_put(envp->hOutFifo, hInBuf) < 0) { ERR("Failed to send buffer to display thread\n"); cleanup(THREAD_FAILURE); } /* Return a buffer to the capture driver */ if (Capture_put(hCapture, hCapBuf) < 0) { ERR("Failed to put capture buffer\n"); cleanup(THREAD_FAILURE); } /* Get a buffer from the video thread */ fifoRet = Fifo_get(envp->hInFifo, &hInBuf); if (fifoRet < 0) { ERR("Failed to get buffer from video thread\n"); cleanup(THREAD_FAILURE); } /* Did the video thread flush the fifo? */ if (fifoRet == Dmai_EFLUSH) { cleanup(THREAD_SUCCESS); } }

（4）修改display.c

同样，由于videnc_copy输出的视频流为YUV422格式，不需要进行转换就可以直接传递给驱动进行显示，所以在display.c中也要修改部分代码。

static Int config(Ccv_Handle hCcv, Blend_Handle hBlend, UI_Handle hUI, Buffer_Handle hSrcBuf, Buffer_Handle hDstBuf, UInt8 trans) { Blend_Config_Params bConfigParams = Blend_Config_Params_DEFAULT; Buffer_Handle hBmpBuf; Int i; #if 0 /* Configure the 420->422 color conversion job */ if (Ccv_config(hCcv, hSrcBuf, hDstBuf) < 0) { ERR("Failed to configure color conversion job\n"); return FAILURE; } #endif …… /* * Color convert the 420Psemi decoded buffer from * the video thread to the 422Psemi display. */ //if (Ccv_execute(hCcv, hSrcBuf, hDstBuf) < 0) { // ERR("Failed to execute color conversion job\n"); // cleanup(THREAD_FAILURE); //}

（5）修改video.c

video.c中的修改较多，只讲一下主要部分。

首先，注释掉与H264编解码相关的变量和参数，添加一些用于videnc_copy的变量。

VIDENC_Handle enc = NULL; String encoderName = "videnc_copy"; VIDENC_InArgs encInArgs; VIDENC_OutArgs encOutArgs; VIDENC_DynamicParams encDynParams; VIDENC_Status encStatus; XDAS_Int8 *inBuf; XDAS_Int8 *encodedBuf; XDM_BufDesc inBufDesc; XDAS_Int8 *src[XDM_MAX_IO_BUFFERS]; XDAS_Int32 inBufSizes[XDM_MAX_IO_BUFFERS]; XDM_BufDesc encodedBufDesc; XDAS_Int8 *encoded[XDM_MAX_IO_BUFFERS]; XDAS_Int32 encBufSizes[XDM_MAX_IO_BUFFERS]; Memory_AllocParams allocParams; encInArgs.size = sizeof(encInArgs); encOutArgs.size = sizeof(encOutArgs); encDynParams.size = sizeof(encDynParams); encStatus.size = sizeof(encStatus); allocParams.type = Memory_CONTIGPOOL; allocParams.flags = Memory_NONCACHED; allocParams.align = BUFALIGN; allocParams.seg = 0; inBuf = (XDAS_Int8 *)Memory_alloc(IFRAMESIZE, &allocParams); encodedBuf = (XDAS_Int8 *)Memory_alloc(EFRAMESIZE, &allocParams); /* clear and initialize the buffer descriptors */ memset(src, 0, sizeof(src[0]) * XDM_MAX_IO_BUFFERS); memset(encoded, 0, sizeof(encoded[0]) * XDM_MAX_IO_BUFFERS); src[0] = inBuf; encoded[0] = encodedBuf; inBufDesc.numBufs = encodedBufDesc.numBufs = 1; inBufDesc.bufSizes = inBufSizes; encodedBufDesc.bufSizes = encBufSizes; inBufSizes[0] = IFRAMESIZE; encBufSizes[0] = EFRAMESIZE; inBufDesc.bufs = src; encodedBufDesc.bufs = encoded;

然后，修改颜色空间定义，从原来的YUV420PSEMI修改为YUV422PSEMI。

gfxAttrs.colorSpace = ColorSpace_YUV422PSEMI; gfxAttrs.dim.width = envp->imageWidth; gfxAttrs.dim.height = envp->imageHeight; gfxAttrs.dim.lineLength = BufferGfx_calcLineLength(gfxAttrs.dim.width, gfxAttrs.colorSpace);

接下来，需要对buffer进行一定修改，再传递给videnc_copy进行处理。

if (!envp->passThrough) { fifoRet = Fifo_get(envp->hDisplayOutFifo, &hDispBuf); memcpy(inBuf, Buffer_getUserPtr(hVidBuf), IFRAMESIZE); #ifdef CACHE_ENABLED #ifdef xdc_target__isaCompatible_64P Memory_cacheWbInv(inBuf, IFRAMESIZE); #else #error Unvalidated config - add appropriate fread-related cache maintenance #endif Memory_cacheInv(encodedBuf, EFRAMESIZE); #endif //memcpy(encodedBuf, inBuf, EFRAMESIZE); ret = VIDENC_process(enc, &inBufDesc, &encodedBufDesc, &encInArgs, &encOutArgs); if (ret < 0) { cleanup(THREAD_FAILURE); } #ifdef CACHE_ENABLED Memory_cacheWb(encodedBuf, EFRAMESIZE); #endif memcpy(Buffer_getUserPtr(hDispBuf), encodedBuf, EFRAMESIZE); Buffer_setNumBytesUsed(hDispBuf, EFRAMESIZE); /* Update global data for user interface */ gblIncVideoBytesProcessed(EFRAMESIZE); if (Fifo_put(envp->hDisplayInFifo, hDispBuf) < 0) { ERR("Failed to send buffer to display thread\n"); cleanup(THREAD_FAILURE); } /* and return input video frame to capture thread */ if (Fifo_put(envp->hCaptureInFifo, hVidBuf) < 0) { ERR("Failed to send buffer to capture thread\n"); cleanup(THREAD_FAILURE); } } else { /* Send the buffer through to the display thread unmodified */ if (Fifo_put(envp->hDisplayInFifo, hVidBuf) < 0) { ERR("Failed to send buffer to display thread\n"); cleanup(THREAD_FAILURE); } }

最后，需要特别注意的是：在上面的代码中使用了Fifo_put(envp->hDisplayInFifo, hDispBuf)将buffer传递给display线程，这就要注释掉后面部分代码，否则程序运行时video线程会阻塞，因为无法从display线程的fifo得到buffer（已经全部传递给capture线程了）。

#if 0 /* Get a buffer from the display thread to send to the capture thread */ if ((ret != Dmai_EFIRSTFIELD) && (Fifo_getNumEntries(envp->hDisplayOutFifo))) { do { fifoRet = Fifo_get(envp->hDisplayOutFifo, &hDispBuf); if (fifoRet < 0) { ERR("Failed to get buffer from video thread\n"); cleanup(THREAD_FAILURE); } /* Did the display thread flush the fifo? */ if (fifoRet == Dmai_EFLUSH) { cleanup(THREAD_SUCCESS); } /* The display thread is no longer using the buffer */ Buffer_freeUseMask(BufTab_getBuf(hBufTab, Buffer_getId(hDispBuf)), /*Buffer_getUseMask(BufTab_getBuf(hBufTab, Buffer_getId(hDispBuf)))*/DISPLAY_FREE); /* Get a free buffer */ hDstBuf = BufTab_getFreeBuf(hBufTab); if (hDstBuf == NULL) { ERR("Failed to get free buffer from BufTab\n"); BufTab_print(hBufTab); cleanup(THREAD_FAILURE); } /* * Reset the dimensions of the buffer in case the decoder has * changed them due to padding. */ BufferGfx_resetDimensions(hDstBuf); /* Send a buffer to the capture thread */ if (Fifo_put(envp->hCaptureInFifo, hDstBuf) < 0) { ERR("Failed to send buffer to capture thread\n"); cleanup(THREAD_FAILURE); } } while (Fifo_getNumEntries(envp->hDisplayOutFifo) > 0); } #endif

1.2 程序运行结果

修改完之后，确认编译通过，然后下载到开发板上运行，串口调试终端输出信息如下所示。



在显示器上的显示效果如下所示，证明程序运行成功。

1.3 遗留问题

从串口终端的输出信息可以看出，DSP端一直处于满负荷状态，视频处理的帧率还没有达到1fps，大约每处理1帧图像需要1.5秒左右的时间。这说明算法的效率很低，后期需要进行很多优化，主要考虑是将所有浮点运算转换为定点运算，因为DM6467的DSP是C64x+型定点DSP，做浮点运算时速度特别低。

另外，可以考虑使用TI提供的DSPLIB、FastRTSLIB、IQMathLIB、IMGLIB和VLIB等库。用VLIB和IMGLIB替换掉MECV中的部分函数，用VLIB进行颜色空间转换，用FastRTS、IQMathLIB和DSPLIB来进行一些基本的数据处理，例如浮点运算、矩阵运算和乘除运算等操作。

以上这些库其实都已经集成到C6Accel中了，所以接下来的工作就是学习使用C6Accel，并将OpenCV集成进去。