Question

我目前正在尝试使用YUV420格式（双平面）在openGL中绘制图像。我收到原始数据，并尝试将其解析为CVPixelBuffer，然后使用CVOpenGLESTextureCacheCreateTextureFromImage传递所述缓冲区。虽然在解析CVPixelBuffer时没有收到任何错误，但在尝试传递给CVOpenGLESTextureCacheCreateTextureFromImage时收到错误（-6683）。我正在尽力遵循Apple的GLCameraRipple示例代码 - 除了我再次使用原始图像数据而不是相机中的数据。

希望有人可以解释我在这里失踪的是什么 - 我认为这是一个缺失的属性......

FYI，平面0是Y平面，平面1是UV平面 - 其中UV平面应该是Y平面宽度和高度的一半。

size_t numPlanes = image->GetNumPlanes();
size_t planeWidth[numPlanes];
size_t planeHeight[numPlanes];
size_t scanWidth[numPlanes];
void *planeIndex[numPlanes];
for(int i = 0; i<numPlanes; i++){
    i<1 ? planeWidth[i] = image->GetWidth() : planeWidth[i] = image->GetWidth()/2;
    i<1 ? planeHeight[i] = image->GetHeight() : planeWidth[i] = image->GetHeight()/2;
    scanWidth[i] = image->GetScanWidth(i);
    planeIndex[i] = image->GetPlanePointer(i);
}

CVPixelBufferRef pixelBuffer;
CFDictionaryRef empty;
CFMutableDictionaryRef attrs;
empty = CFDictionaryCreate(kCFAllocatorDefault,
                           NULL,
                           NULL,
                           0,
                           &kCFTypeDictionaryKeyCallBacks,
                           &kCFTypeDictionaryValueCallBacks);

attrs = CFDictionaryCreateMutable(kCFAllocatorDefault,
                                  1,
                                  &kCFTypeDictionaryKeyCallBacks,
                                  &kCFTypeDictionaryValueCallBacks);

CFDictionarySetValue(attrs, kCVPixelBufferIOSurfacePropertiesKey, empty);



CVReturn cvError = CVPixelBufferCreateWithPlanarBytes(kCFAllocatorDefault,
                                                      image->GetWidth(),
                                                      image->GetHeight(),
                                                      kCVPixelFormatType_420YpCbCr8BiPlanarFullRange,
                                                      nil,
                                                      nil,
                                                      numPlanes,
                                                      planeIndex,
                                                      planeWidth,
                                                      planeHeight,
                                                      scanWidth,
                                                      nil, nil, attrs, &pixelBuffer);
if(cvError) NSLog(@"Error at CVPixelBufferCreateWithPlanarBytes:  %d", cvError);

CVReturn err;
size_t width = CVPixelBufferGetWidth(pixelBuffer);
size_t height = CVPixelBufferGetHeight(pixelBuffer);

if (!_videoTextureCache)
{
    NSLog(@"No video texture cache");
    return;
}

if (_bModel == nil ||
    width != _textureWidth ||
    height != _textureHeight)
{
    _textureWidth = width;
    _textureHeight = height;

    _bModel = [[BufferModel alloc] initWithScreenWidth:_screenWidth
                                          screenHeight:_screenHeight
                                            meshFactor:_meshFactor
                                          textureWidth:_textureWidth
                                         textureHeight:_textureHeight];

    [self setupBuffers];
}

[self cleanUpTextures];

// CVOpenGLESTextureCacheCreateTextureFromImage will create GLES texture
// optimally from CVImageBufferRef.

// Y-plane
glActiveTexture(GL_TEXTURE0);
err = CVOpenGLESTextureCacheCreateTextureFromImage(kCFAllocatorDefault,
                                                   _videoTextureCache,
                                                   pixelBuffer,
                                                   NULL,
                                                   GL_TEXTURE_2D,
                                                   GL_RED_EXT,
                                                   _textureWidth,
                                                   _textureHeight,
                                                   GL_RED_EXT,
                                                   GL_UNSIGNED_BYTE,
                                                   0,
                                                   &_lumaTexture);
if (err)
{
    NSLog(@"Error at CVOpenGLESTextureCacheCreateTextureFromImage %d", err);
}

感谢能够提供帮助的任何人。虽然我知道存在类似的问题（不完全相同），但所述问题也很老，从未收到任何回复。我希望能为我的情况带来更多好运。

Answer 1

您创建的CVPixelBuffer中的iosurface属性为null。

手动创建：

<CVPixelBuffer 0x1fd52790 width=1280 height=720 pixelFormat=420v iosurface=0x0 planes=2>

由CMSampleBufferGetImageBuffer创建：

<CVPixelBuffer 0x1fd521e0 width=1280 height=720 pixelFormat=420f iosurface=0x21621c54 planes=2>

据我所知，没有解决方案。

Answer 2

如果要将CVPixelBufferCreate与OpenGL一起使用，请使用CVPixelBufferRef。它为您创建了一个iosurface，与WithBytes替代品不同。缺点是您无法重用现有的缓冲区。您必须将现有缓冲区中的数据复制到新分配的缓冲区中。

// set pixel buffer attributes so we get an iosurface
NSDictionary *pixelBufferAttributes = [NSDictionary dictionaryWithObjectsAndKeys:
                                       [NSDictionary dictionary], kCVPixelBufferIOSurfacePropertiesKey,
                                       nil];

// create planar pixel buffer
CVPixelBufferRef pixelBuffer = nil;
CVPixelBufferCreate(kCFAllocatorDefault, bufferYUV.width, bufferYUV.height, kCVPixelFormatType_420YpCbCr8BiPlanarFullRange, (CFDictionaryRef)pixelBufferAttributes, &pixelBuffer);

// lock pixel buffer
CVPixelBufferLockBaseAddress(pixelBuffer, 0);

// get image details
size_t width = CVPixelBufferGetWidth(pixelBuffer);
size_t height = CVPixelBufferGetHeight(pixelBuffer);

// get plane addresses
unsigned char *baseAddressY  = CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0);
unsigned char *baseAddressUV = CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 1);

//TODO: copy your data buffers to the newly allocated memory locations

// unlock pixel buffer address
CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);

// intialize buffers if not already initialized (see GLCameraRipple example)
if (!_buffersInitialized)
{
    [self initializeBuffersWithTextureWidth:width textureHeight:height];
}

// always clean up last textures
CVReturn err;
[self cleanUpTextures];

// Y-plane
glActiveTexture(GL_TEXTURE0);
err = CVOpenGLESTextureCacheCreateTextureFromImage(kCFAllocatorDefault, _videoTextureCache, pixelBuffer, NULL, GL_TEXTURE_2D, GL_RED_EXT, width, height, GL_RED_EXT, GL_UNSIGNED_BYTE, 0, &_lumaTexture);
if (err)
{
    NSLog(@"Could not create Y texture from image. %d", err);
}

glBindTexture(CVOpenGLESTextureGetTarget(_lumaTexture), CVOpenGLESTextureGetName(_lumaTexture));
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

// UV-plane
glActiveTexture(GL_TEXTURE1);
err = CVOpenGLESTextureCacheCreateTextureFromImage(kCFAllocatorDefault, _videoTextureCache, pixelBuffer, NULL, GL_TEXTURE_2D, GL_RG_EXT, width / 2, height / 2, GL_RG_EXT, GL_UNSIGNED_BYTE, 1, &_chromaTexture);
if (err)
{
    NSLog(@"Could not create UV texture from image. %d", err);
}

glBindTexture(CVOpenGLESTextureGetTarget(_chromaTexture), CVOpenGLESTextureGetName(_chromaTexture));
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

Answer 3

我不会在YUV上尝试以下方法，但它适用于RGB情况

https://developer.apple.com/library/ios/qa/qa1781/_index.html

如果启用了ARC，则在CFDictionaryRef之前添加__bridge。

CVOpenGLESTextureCacheCreateTextureFromImage返回错误6683

3 个答案: