基本流程
代码示例
// WindowsProject1.cpp : 定义应用程序的入口点。
//
#include "framework.h"
#include "WindowsProject1.h"
#include
#define MAX_LOADSTRING 100
// 全局变量:
HINSTANCE hInst; // 当前实例
WCHAR szTitle[MAX_LOADSTRING]; // 标题栏文本
WCHAR szWindowClass[MAX_LOADSTRING]; // 主窗口类名
// 此代码模块中包含的函数的前向声明:
ATOM MyRegisterClass(HINSTANCE hInstance);
BOOL InitInstance(HINSTANCE, int);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
INT_PTR CALLBACK About(HWND, UINT, WPARAM, LPARAM);
void Render();
int APIENTRY wWinMain(_In_ HINSTANCE hInstance,
_In_opt_ HINSTANCE hPrevInstance,
_In_ LPWSTR lpCmdLine,
_In_ int nCmdShow)
{
UNREFERENCED_PARAMETER(hPrevInstance);
UNREFERENCED_PARAMETER(lpCmdLine);
// TODO: 在此处放置代码。
// 初始化全局字符串
LoadStringW(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
LoadStringW(hInstance, IDC_WINDOWSPROJECT1, szWindowClass, MAX_LOADSTRING);
MyRegisterClass(hInstance);
// 执行应用程序初始化:
if (!InitInstance(hInstance, nCmdShow))
{
return FALSE;
}
HACCEL hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_WINDOWSPROJECT1));
MSG msg;
// 主消息循环:
while (GetMessage(&msg, nullptr, 0, 0))
{
// 如果消息可得到,返回非零值;如果没有消息可得到,返回值是零。
if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
else
{
Sleep(40);
Render();
}
}
return (int)msg.wParam;
}
ATOM MyRegisterClass(HINSTANCE hInstance)
{
WNDCLASSEXW wcex;
// 注册窗口类型
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_WINDOWSPROJECT1));
wcex.hCursor = LoadCursor(nullptr, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
wcex.lpszMenuName = MAKEINTRESOURCEW(IDC_WINDOWSPROJECT1);
wcex.lpszClassName = szWindowClass;
wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL));
return RegisterClassExW(&wcex);
}
const SSIZE_T pic_width = 320;
const SSIZE_T pic_height = 180;
static HWND g_hwnd;
static FILE* g_fp;
void Render();
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
hInst = hInstance; // 将实例句柄存储在全局变量中
HWND hWnd = CreateWindowW(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
100, 100, pic_width, pic_height, nullptr, nullptr, hInstance, nullptr);
if (!hWnd)
{
return FALSE;
}
ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);
g_hwnd = hWnd;
int err = fopen_s(&g_fp, "./test_rgb24_320x180.rgb", "rb+");
if (err)
{
printf_s("%d", err);
fprintf(stderr, "Can't Open Source File \n");
getchar();
exit(-1);
}
MSG msg;
ZeroMemory(&msg, sizeof(MSG));
while (msg.message != WM_QUIT)
{
if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
else
{
Sleep(40);
Render();
}
}
return TRUE;
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;
}
static unsigned char buffer[pic_width * pic_height * 8];
void CHANGE_ENDIAN_PIC(unsigned char* image, const SSIZE_T pic_width, const SSIZE_T pic_height, int i);
void Render()
{
// 在结束后重新播放
if (fread(buffer, 1, pic_height * pic_width * 24 / 8, g_fp) != pic_height * pic_width * 24 / 8)
{
fseek(g_fp, 0, SEEK_SET);
fread(buffer, 1, pic_height * pic_width * 24 / 8, g_fp);
}
HDC hdc = GetDC(g_hwnd);
CHANGE_ENDIAN_PIC(buffer, pic_width, pic_height, 24);
RECT rect;
GetWindowRect(g_hwnd, &rect);
size_t screen_w = rect.right - rect.left;
size_t screen_h = rect.bottom - rect.top;
BITMAPINFO bmpInfo = {0};
DWORD dwBmpHdr = sizeof(BITMAPINFO);
// BMP格式
bmpInfo.bmiHeader.biBitCount = 24; // 每个像素是8bit,RGB三个像素为24bit
bmpInfo.bmiHeader.biClrImportant = 0;
bmpInfo.bmiHeader.biSize = dwBmpHdr;
bmpInfo.bmiHeader.biSizeImage = 0;
bmpInfo.bmiHeader.biWidth = pic_width;
bmpInfo.bmiHeader.biHeight = -pic_height;
bmpInfo.bmiHeader.biXPelsPerMeter = 0;
bmpInfo.bmiHeader.biYPelsPerMeter = 0;
bmpInfo.bmiHeader.biClrUsed = 0;
bmpInfo.bmiHeader.biPlanes = 1;
bmpInfo.bmiHeader.biCompression = BI_RGB;
int nResult = StretchDIBits(hdc, 0, 0, screen_w, screen_h, 0, 0, pic_width, pic_height, buffer, &bmpInfo,
DIB_RGB_COLORS, SRCCOPY);
ReleaseDC(g_hwnd, hdc);
}
void CHANGE_ENDIAN_24(unsigned char* data)
{
char temp2 = data[2];
data[2] = data[0];
data[0] = temp2;
}
void CHANGE_ENDIAN_PIC(unsigned char* image, const SSIZE_T w, const SSIZE_T h, int bpp)
{
unsigned char* pixeldata = NULL;
for (int i = 0; i < h; i++)
for (int j = 0; j < w; j++)
{
pixeldata = image + (i * w + j) * bpp / 8;
if (bpp == 24)
{
CHANGE_ENDIAN_24(pixeldata);
}
}
}
需要注意的就是位图的格式,很多的视频播放都是转换为位图,比如 RGB 需要转换为 BGR , 以及大小端的调整。