使用Cocoa的Photoshop插件-如何获得预览

Question

我在Mac上实现了一个Photoshop插件，而且我使用的是Cocoa。到目前为止一切正常，但下一步是提供一个“预览”图像，作为我插件窗口的一部分，我被卡住了。我是一个n00b Obj-C程序员，这对我没有什么帮助:-)

到目前为止，我已经得到了类似这样的东西：

int dataSize = gFilterRecord->bigDocumentData->wholeSize32.v *
               gFilterRecord->bigDocumentData->wholeSize32.h *
               gFilterRecord->planes; 

NSData *inData = [[NSData alloc] initWithBytesNoCopy:gFilterRecord->inData length:dataSize freeWhenDone:NO];
NSLog(@"LoadImageFromSDK : Data created");
NSImage *imageTmp = [[NSImage alloc] initWithData:inData];
NSLog(@"LoadImageFromSDK : Image created");

//Save to PNG file as a test of this image creation
[[imageTmp TIFFRepresentation] writeToFile:@"/tmp/imageTmp.tif" atomically:YES];
NSLog(@"LoadImageFromSDK : Wrote image to disk");

此时此刻，它可怕地崩溃了：

 09/07/22 10:23:32 AM Adobe Photoshop Elements[46628] \*\*\* NSCopyMemoryPages(0x0, 0x245f4000, 2265088) failed 

我可能计算错了inData的大小。帮助?

另外，NSImage是否能够正确解释图像数据blob？或者我应该放弃它，只需要逐个像素地映射到NSImage中？

Answer 1

好吧，这比我预期的要痛苦得多。另外，感谢NVidia发布了这个PDF，它比实际的SDK文档更好地解释了Photoshop SDK的过滤记录。

这段代码实际读取inData并生成一个可用的NSImage (大量日志记录只是为了弄清楚它在做什么，可以随意删除)，以及用于调试目的的示例tif文件。

NSLog(@"Entering LoadImageFromSDK");

unsigned char *bitmapPlanes[4];    
bitmapPlanes[0] = (unsigned char *) (gFilterRecord->inData);

NSLog(@"Params to create bitmap");
NSLog(@"pixelsWide = %d", gFilterRecord->bigDocumentData->imageSize32.h );
NSLog(@"pixelsHigh = %d", gFilterRecord->bigDocumentData->imageSize32.v );
NSLog(@"bitsPerSample = %d", gFilterRecord->depth );
NSLog(@"samplesPerPixel = %d", gFilterRecord->planes );
NSLog(@"hasAlpha = %d", NO );
NSLog(@"isPlanar = %d", NO );
NSLog(@"colorSpaceName = %@", mapImageModeToColorSpace(gFilterRecord->imageMode) );
NSLog(@"bytesPerRow = %d", gFilterRecord->inRowBytes );
NSLog(@"bitsPerPixel = %d", gFilterRecord->depth*gFilterRecord->planes );    

NSBitmapImageRep *bitmapTmp = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:bitmapPlanes
                                                                      pixelsWide:gFilterRecord->bigDocumentData->imageSize32.h
                                                                      pixelsHigh:gFilterRecord->bigDocumentData->imageSize32.v
                                                                   bitsPerSample:gFilterRecord->depth
                                                                 samplesPerPixel:gFilterRecord->planes
                                                                        hasAlpha:NO 
                                                                        isPlanar:NO 
                                                                  colorSpaceName:mapImageModeToColorSpace(gFilterRecord->imageMode) 
                                                                     bytesPerRow:gFilterRecord->inRowBytes
                                                                    bitsPerPixel:gFilterRecord->depth*gFilterRecord->planes];

NSLog(@"LoadImageFromSDK : Bitmap created = %@", bitmapTmp);

[[bitmapTmp TIFFRepresentation] writeToFile:@"/Users/someuser/temp/sample.tif" atomically:YES];


NSImage *imageTmp = [[NSImage alloc] initWithSize:[bitmapTmp size]];
[imageTmp addRepresentation:bitmapTmp];
NSLog(@"LoadImageFromSDK : Image created = %@", imageTmp);