stride

Anyone know what Scan0 and Stride for? I need a good explanation Thanks. Are you talking about the BitmapData class? If so, the description in the documentation is reasonably clear, I think: Scan0 : Gets or sets the address of the first pixel data in the bitmap. This can also be thought of as the first scan line in the bitmap. In other words, this lets you find the data to examine or change - or even lets you make the bitmap to a completely different piece of data. Stride : The stride is the width of a single row of pixels (a scan line), rounded up to a four-byte boundary. If the stride is

I know what meaning stride has when it is just an integer number (by which step you should apply filter to image). But what about (1, 1) or even more dimensional stride? The stride defines how the filter is moved along the input image (tensor). Nothing stops you from striding along different axes differently, e.g., stride=[1, 2] means move 1px at a time along 0 axis, and 2px at a time along 1 axis. This particular combination isn't common, but possible. Tensorflow API goes even further and allows custom striding for all axes of the 4D input tensor (see tf.nn.conv2d ). Using this API it's not

I tried to find what each cell of AVFrame.linesize[] means, but I didn't found. As I understood linesize[0] is the width, linesize[1] is the height. If I'm right what does other cells mean? why after avcodec_decode_video2(codecCtxDecode, frameDecoded, &frameFinished, &packet); only linesize[0] has the value and other cells are always 0? UPDATED I think AVFrame.data[i] and AVFrame.linesize[i] are the data of specific color in the row and the length of the row, am I correct? pogorskiy In the case of planar data, such as YUV420 , linesize[i] contains stride for the i -th plane. For example, for

I am currently going through numpy and there is a topic in numpy called "strides". I understand what it is. But how does it work? I did not find any useful information online. Can anyone let me understand in a layman's terms? The actual data of a numpy array is stored in a homogeneous and contiguous block of memory called data buffer. For more information see NumPy internals . Using the (default) row-major order, a 2D array looks like this: To map the indices i,j,k,... of a multidimensional array to the positions in the data buffer (the offset, in bytes), NumPy uses the notion of strides .

I was looking for the fastest way to convert a Bitmap to 8bpp. I found 2 ways: 1. public static System.Drawing.Image ConvertTo8bpp(Bitmap oldbmp) { using (var ms = new MemoryStream()) { oldbmp.Save(ms, ImageFormat.Gif); ms.Position = 0; return System.Drawing.Image.FromStream(ms); } } 2. http://www.wischik.com/lu/programmer/1bpp.html But: 1. Results in a very low quality result (bad pallet) and 2 gives me a Bitmap with negative stride, when I try to lockbits and copy the data to a byte array I get an exception: Attempted to read or write protected memory. This is often an indication that other

I'm trying to get an bitmap created from raw data to show in WPF, by using an Image and a BitmapSource: Int32[] data = new Int32[RenderHeight * RenderWidth]; for (Int32 i = 0; i < RenderHeight; i++) { for (Int32 j = 0; j < RenderWidth; j++) { Int32 index = j + (i * RenderHeight); if (i + j % 2 == 0) data[index] = 0xFF0000; else data[index] = 0x00FF00; } } BitmapSource source = BitmapSource.Create(RenderWidth, RenderHeight, 96.0, 96.0, PixelFormats.Bgr32, null, data, 0); RenderImage.Source = source; However the call to BitmapSource.Create throws an ArgumentException, saying "Value does not fall