buffer

问题 How, can I have a buffer or array of images "Mat" with OpenCV? I mean: having a set of images, want to pick up and put in an array like How can I do this? It's like C++ normal array style? Mat images[2]; images[0] = imread(...); images[1] = imread(..); Thanks in advance. 回答1: Just declare a array of cvMat object as- Mat image_array[10]; // array of 10 images Now read the images into it according to index of the array image_array[0]=imread("/home/me/Pictures/img1.png",1); image_array[1]=imread

问题 I recently debugged a performance issue with how I was using SslStream. The client is C#/.NET and had the following Stream configuration Raw Socket/NetStream Wrapped by BufferedStream Wrapped by SslStream Wrapped by "protocol" stream (which sends bytes/ints/strings etc) I was seeing extremely slow performance when sending data from a client to a server, across the internet where it was taking a long time to serialise information on the client side. Removing SSL stream and the connection sped

问题 My problem is similar to python - How select.select() works? . However, the solution there doesn't work for me, because I'm not open()ing my file. Instead, it's a socket. I couldn't find any way to set it to be unbuffered in the documentation. I have a glib mainloop (which uses select), where I registered the socket for reading. Because socket.recv() requires me to specify a receive buffer size, it is not unusual to read fewer bytes than the socket read. As long as the kernel buffers them,

问题 I have this Program: #include <stdio.h> #include <string.h> #include <stdlib.h> void main(void) { char *buffer1 = malloc(sizeof(char)); char *buffer2 = malloc(sizeof(char)); strcpy(buffer2, "AA"); printf("before: buffer1 %s\n", buffer1); printf("before: buffer2 %s\n", buffer2); printf("address, buffer1 %p\n", &buffer1); printf("address, buffer2 %p\n", &buffer2); strcpy(buffer1, "BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB"); printf("after: buffer1 %s\n", buffer1); printf("after: buffer2 %s\n", buffer2)

问题 I am trying to use a buffer in a compute shader like this: layout (binding = 1, std430) writeonly buffer bl1 { uint data[gl_WorkGroupSize.x * gl_NumWorkGroups.x * gl_NumWorkGroups.y]; }; but I get the following error (because of using gl_NumWorkGroups for the size): Array size must be a constant integer expression How can I work around this? 回答1: Stop putting in a length at all: layout (binding = 1, std430) writeonly buffer bl1 { uint data[]; }; This is a feature unique to SSBOs. And you can

问题 I need a reasonable supply of high-quality random data for an application I'm writing. Linux provides the /dev/random file for this purpose which is ideal; however, because my server is a single-service virtual machine, it has very limited sources of entropy, meaning /dev/random quickly becomes exhausted. I've noticed that if I read from /dev/random, I will only get 16 or so random bytes before the device blocks while it waits for more entropy: [duke@poopz ~]# hexdump /dev/random 0000000 f4d3

问题 I'm using this tutorial for building a multiplayer game that uses Bluetooth for connection: https://developer.android.com/samples/BluetoothChat/index.html Since I'm sending long stings in JSON format (like 5500+ in length) the message handler method is not returning the entire strings I send, and instead it splits them into 989 character long strings (its always 989 characters in length). The problem is, when I try to parse the JSON string, obviously it throws an error, because the text is

问题 I saw many examples on the web (for example) which do the following Create and Bind FBO Create and Bind BUFFERS (texture, render, depth, stencil) Then, UnBind BUFFERS To work with FBO- Bind FBO, do the work then UnBind FBO However, also Bind texture BUFFER for read, write etc. with texture BUFFER BUT NEVER EVER SEEN re-Bind of other BUFFERS (render, depth, stencil), Why? Example of BUFFERS creation and bind/unbind (Below code is just for example only to show what I explained and works

问题 Suppose that this file is 2 and 1/2 blocks long, with block size of 1024. aBlock = 1024; char* buffer = new char[aBlock]; while (!myFile.eof()) { myFile.read(buffer,aBlock); //do more stuff } The third time it reads, it is going to write half of the buffer, leaving the other half with invalid data. Is there a way to know how many bytes did it actually write to the buffer? 回答1: istream::gcount returns the number of bytes read by the previous read. 回答2: Your code is both overly complicated and

问题 In Emacs 21.x I don't know if via a specific customization of split-window or due to a different default behaviour by Emacs, invoking the split-window-below besides splitting the window, it switched the buffer in the non-focused window to the next buffer. Currently (Emacs 24.x), the split-window and siblings split-window-below and split-window-right don't seem to allow such a customization. Is this true? If so, how to tweak Emacs to have this behaviour? Redefining split-window or split-window