音視頻入門-09-RGB&YUV互轉-使用開源庫
- 2019 年 10 月 3 日
- 筆記
介紹開源庫
使用第三方開源庫來簡化開發，屏蔽一些底層的複雜度，節省大量編寫代碼的時間。
libyuv： Google 開源的實現各種 YUV 與 RGB 之間相互轉換、旋轉、縮放的庫。
yuv2rgb：C library for fast image conversion between yuv420p and rgb24.
使用開源庫
libyuv
FFmpeg 生成代碼所需文件：
ffmpeg -i rainbow.bmp -video_size 700x700 -pix_fmt yuv444p rainbow-yuv444p.yuv ffmpeg -i rainbow.bmp -video_size 700x700 -pix_fmt yuv420p rainbow-yuv420p.yuv ffmpeg -i rainbow.bmp -video_size 700x700 -pix_fmt rgb24 rainbow-rgb24.rgbYUV444P to RGB32
將 FFmpeg 生成的 YUV444P 格式轉換成 RGB32 格式。
[rainbow-yuv444p.yuv] -> [rainbow-yuv444p-to-rgb32-libyuv.rgb]
#include <stdio.h> #include "libyuv.h" void libyuv_I444_to_Rgb(char *srcFileName, char *dstFileName, int width, int height) { FILE *src_file = fopen(srcFileName, "rb"); FILE *dst_file = fopen(dstFileName, "wb"); int size_src = width * height * 3; int size_dest = width * height * 4; char *buffer_src = (char *)malloc(size_src); char *buffer_dest = (char *)malloc(size_dest); fread(buffer_src, 1, size_src, src_file); I444ToARGB( (const u_int8_t*)buffer_src, width, (const u_int8_t*)(buffer_src + width * height), width, (const u_int8_t*)(buffer_src + 2 * width * height), width, (u_int8_t*)buffer_dest, width * 4, width, height); fwrite(buffer_dest, 1, size_dest, dst_file); free(buffer_src); free(buffer_dest); fclose(dst_file); fclose(src_file); } int main() { int width = 700, height = 700; libyuv_I444_to_Rgb("/Users/staff/Desktop/rainbow-yuv444p.yuv", "/Users/staff/Desktop/rainbow-yuv444p-to-rgb32-libyuv.yuv", width, height); return 0; }FFplay 顯示生成的 rainbow-yuv444p-to-rgb32-libyuv.rgb
ffplay -f rawvideo -pixel_format rgb32 -video_size 700x700 rainbow-yuv444p-to-rgb32-libyuv.rgb
RGB24 to YUV420p
將 FFmpeg 生成的 RGB24 格式轉換成 YUV420p 格式。
[rainbow-rgb24.rgb] -> [rainbow-rgb24-to-yuv420p-libyuv.yuv]
#include <stdio.h> #include "libyuv.h" void libyuv_Rgb24_to_Yuv420p(char *rgbFileName, char *yuvFileName, int width, int height) { FILE *rgb_file = fopen(rgbFileName, "rb"); FILE *yuv_file = fopen(yuvFileName, "wb"); int size_rgb = width * height * 3; int size_yuv = width * height * 3 / 2; uint8_t *buffer_rgb = (uint8_t *)malloc(size_rgb); uint8_t *buffer_yuv = (uint8_t *)malloc(size_yuv); fread(buffer_rgb, 1, size_rgb, rgb_file); // RGB to BGR // uint8_t temp; // for(int i = 0; i < size_rgb; i+=3) { // temp = buffer_rgb[i + 0]; // buffer_rgb[i + 0] = buffer_rgb[i + 2]; // buffer_rgb[i + 2] = temp; // } // RGB24ToI420( RAWToI420( buffer_rgb, width*3, buffer_yuv, width, buffer_yuv + width*height, (width+1)/2, buffer_yuv + width*height + ((width+1)/2)*((height+1)/2), (width+1)/2, width, height); fwrite(buffer_yuv, 1, size_yuv, yuv_file); free(buffer_rgb); free(buffer_yuv); fclose(yuv_file); fclose(rgb_file); } int main() { int width = 700, height = 700; libyuv_Rgb24_to_Yuv420p("/Users/staff/Desktop/rainbow-rgb24.rgb", "/Users/staff/Desktop/rainbow-rgb24-to-yuv420p-libyuv.yuv", width, height); return 0; }FFplay 顯示生成的 rainbow-rgb24-to-yuv420p-libyuv.yuv
ffplay -f rawvideo -pixel_format yuv420p -video_size 700x700 rainbow-rgb24-to-yuv420p-libyuv.yuv
descampsa/yuv2rgb
YUV420p to RGB24
將 FFmpeg 生成的 YUV420P 格式轉換成 RGB24 格式。
[rainbow-yuv420p.yuv] -> [rainbow-yuv420p-to-rgb24-descampsa.rgb]
#include <stdio.h> #include "descampsa/yuv2rgb/yuv_rgb.h" void yuv420pToRgb24(uint8_t *YUV, uint8_t *RGB, uint32_t width, uint32_t height) { const YCbCrType yuv_format = YCBCR_601; // const YCbCrType yuv_format = YCBCR_709; // const YCbCrType yuv_format = YCBCR_JPEG; yuv420_rgb24_std( width, height, YUV, YUV+width*height, YUV+width*height+((width+1)/2)*((height+1)/2), width, (width+1)/2, RGB, width*3, yuv_format); } int main() { uint32_t width = 700, height = 700; uint8_t RGB[width*height*3]; uint8_t YUV[width*height*3/2]; FILE *yuv420pFile = fopen("/Users/staff/Desktop/rainbow-yuv420p.yuv", "rb"); fread(YUV, sizeof(YUV), 1, yuv420pFile); yuv420pToRgb24(YUV, RGB, width, height); FILE *rgb24File = fopen("/Users/staff/Desktop/rainbow-yuv420p-to-rgb24-descampsa.rgb", "wb"); fwrite(RGB, sizeof(RGB), 1, rgb24File); fclose(rgb24File); fclose(yuv420pFile); return 0; }FFplay 顯示生成的 rainbow-yuv420p-to-rgb24-descampsa.rgb
ffplay -f rawvideo -pixel_format rgb24 -video_size 700x700 rainbow-yuv420p-to-rgb24-descampsa.rgb
RGB24 to YUV420p
將 FFmpeg 生成的 RGB24 格式轉換成 YUV420p 格式。
[rainbow-rgb24.rgb] -> [rainbow-rgb24-to-yuv420p-descampsa.yuv]
#include <stdio.h> #include "descampsa/yuv2rgb/yuv_rgb.h" void rgb24ToYuv420p(uint8_t *RGB, uint8_t *YUV, uint32_t width, uint32_t height) { const YCbCrType yuv_format = YCBCR_601; // const YCbCrType yuv_format = YCBCR_709; //const YCbCrType yuv_format = YCBCR_JPEG; rgb24_yuv420_std( width, height, RGB, width*3, YUV, YUV+width*height, YUV+width*height+((width+1)/2)*((height+1)/2), width, width/2, yuv_format); } int main() { uint32_t width = 700, height = 700; uint8_t RGB[width*height*3]; uint8_t YUV[width*height*3/2]; FILE *rgb24File = fopen("/Users/staff/Desktop/rainbow-rgb24.rgb", "rb"); fread(RGB, sizeof(RGB), 1, rgb24File); rgb24ToYuv420p(RGB, YUV, width, height); FILE *yuvFile = fopen("/Users/staff/Desktop/rainbow-rgb24-to-yuv420p-descampsa.yuv", "wb"); fwrite(YUV, sizeof(YUV), 1, yuvFile); fclose(rgb24File); fclose(yuvFile); return 0; }FFplay 顯示生成的 rainbow-rgb24-to-yuv420p-descampsa.yuv
ffplay -f rawvideo -pixel_format yuv420p -video_size 700x700 rainbow-rgb24-to-yuv420p-descampsa.yuv
參考資料：
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