[Android] screenshot capture and format conversion in the Android Simulator

1. simulator information Android simulator mobile phone color depth is 16 bit, that is, R/G/B = 5/6/5. Therefore, some special processing is required to obtain the screen image. We can log on to the Android simulator using adb. First, dump the/dev/fb0 content, and then copy the dump file to PC (ubuntu) and run the convert command to process it. The mem is: 614400The line_length is: 640The xres is: 320The yres is: 480bits_per_pixel is: 16 II. screenshot and conversion process 1) get the framebuffer content on the Android phone: # cat/dev/graphics/fb0>/mnt/sdcard/fb0 2) copy the file to the/tmp directory on the PC: $ adb pull/mnt/sdcard/fb0/tmp/fb0 3) extract the content of the first screen from the/tmp/fb0 file (normally there will be 2 to 3 screens ): $ dd bs = 307200 count = 1 if =/tmp/fb0 of =/tmp/screenshot1.xmp cause: the cell phone screen resolution is 320*480; color Depth: 16 bits (R/G/B = 5/6/5), that is, 2 words So there are 320*480*2 = 307200 www.2cto.com or execute in shell: $ echo $ (320*480*2) the image obtained here is in pixmap format. dd command: Use a block of the specified size to copy an object, and convert if = file // input the file name at the same time. The default value is standard input. Of = file // output file name. The default value is standard output. Ibs = bytes // read bytes at a time (that is, the size of a block is bytes ). Obs = bytes // write bytes at a time (that is, the size of a block is bytes ). Bs = bytes // set the size of the read/write block to bytes at the same time, which can replace ibs and obs. Cbs = bytes // One-time conversion of bytes, that is, the size of the conversion buffer. Skip = blocks // you can skip blocks from the beginning of the input file before copying them. Seek = blocks // skip blocks from the beginning of the output file and then start copying. (Usually only valid when the output file is a disk or tape) count = blocks // copy only blocks. The block size is equal to the number of bytes specified by ibs. 4) at this time, the screenshot data is converted into raw image data with 8 bits in each color value. The principle is as follows: [html] int main (int argc, char * argv []) {unsigned short in; // 16bit unsigned char out [3]; // 8bit * 3 while (read (0, & in, 2) = 2) {out [2] = (in & 0x1f) <3; // 5 shift 3 = 8 out [1] = (in> 5) & 0x3f) <2; // 6 shift 2 = 8 out [0] = (in> 11) & 0x1f) <3; // 5 shift 3 = 8 write (1, out, 3);} return 0;} compile the above Code into the execution file/tmp/565to88 and then execute: $/tmp/565to888 </tmp /Screenshot1.xmp>/tmp/screenshot888.xmp converts the color to 24-bit color depth. 5) convert the 24-bit deep-color image to PNG format: $/usr/bin/convert-depth 8-size 320x480 rgb: screenshot888.xmp screenshot.png 6)now you can use the following command to upload the screenshot (screenshot.png: $/usr/bin/display screenshot.png