Hi,
I am having a problem with LoadPic dealing with streaming images. Basically, I modified the code so that it would read jpeg image and then display the image insquence like a movie. But I'm having making it load faster or smoother. My goal to make it display 15 images per sec if possible. Plz take a look.
//---------------part of the code--------------------------------//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
char buf[64];
i = i%9;
sprintf(buf,"frame%06d.jpg",i+1); LoadPictureFile(buf);
hdc = BeginPaint(hWnd, &ps);
if (gpPicture)
{
// get width and height of picture
long hmWidth;
long hmHeight;
gpPicture->get_Width(&hmWidth);
gpPicture->get_Height(&hmHeight);
// convert himetric to pixels
int nWidth = MulDiv(hmWidth, GetDeviceCaps(hdc, LOGPIXELSX), HIMETRIC_INCH);
int nHeight = MulDiv(hmHeight, GetDeviceCaps(hdc, LOGPIXELSY), HIMETRIC_INCH);
RECT rc;
GetClientRect(hWnd, &rc);
// display picture using IPicture::Render
gpPicture->Render(hdc, 0, 0, nWidth, nHeight, 0, hmHeight, hmWidth, -hmHeight, &rc);
}
EndPaint(hWnd, &ps);
i = i+1;
return DefWindowProc(hWnd, message, wParam, lParam);
}
//----------------------part of the code end-----------------------------//
My loadpic program
// LoadPic.cpp : Defines the entry point for the application.
//
#include "stdafx.h"
#include "resource.h"
#include <fstream.h>
#include <string>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
int i = 1;
#define MAX_LOADSTRING 100
#define HIMETRIC_INCH 2540
#define MAP_LOGHIM_TO_PIX(x,ppli) ( ((ppli)*(x) + HIMETRIC_INCH/2) / HIMETRIC_INCH )
// Global Variables:
HINSTANCE hInst; // current instance
TCHAR szTitle[MAX_LOADSTRING]; // The title bar text
TCHAR szWindowClass[MAX_LOADSTRING]; // The title bar text
LPPICTURE gpPicture;
HWND ghWnd;
// Foward declarations of functions included in this code module:
ATOM MyRegisterClass(HINSTANCE hInstance);
BOOL InitInstance(HINSTANCE, int);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
// TODO: Place code here.
MSG msg;
// Initialize global strings
LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
LoadString(hInstance, IDC_LOADPIC, szWindowClass, MAX_LOADSTRING);
MyRegisterClass(hInstance);
// Perform application initialization:
if (!InitInstance (hInstance, nCmdShow))
{
return FALSE;
}
// Main message loop:
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
if (gpPicture)
gpPicture->Release();
return msg.wParam;
}
ATOM MyRegisterClass(HINSTANCE hInstance)
{
WNDCLASSEX wcex;
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = (WNDPROC)WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(hInstance, (LPCTSTR)IDI_LOADPIC);
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
wcex.lpszMenuName = (LPCSTR)IDC_LOADPIC;
wcex.lpszClassName = szWindowClass;
wcex.hIconSm = LoadIcon(wcex.hInstance, (LPCTSTR)IDI_SMALL);
return RegisterClassEx(&wcex);
}
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
HWND hWnd;
hInst = hInstance; // Store instance handle in our global variable
gpPicture = NULL;
ghWnd = hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);
if (!hWnd)
{
return FALSE;
}
ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);
return TRUE;
}
// This function loads a file into an IStream.
void LoadPictureFile(LPCTSTR szFile)
{
// open file
HANDLE hFile = CreateFile(szFile, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL);
_ASSERTE(INVALID_HANDLE_VALUE != hFile);
// get file size
DWORD dwFileSize = GetFileSize(hFile, NULL);
_ASSERTE(-1 != dwFileSize);
LPVOID pvData = NULL;
// alloc memory based on file size
HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, dwFileSize);
_ASSERTE(NULL != hGlobal);
pvData = GlobalLock(hGlobal);
_ASSERTE(NULL != pvData);
DWORD dwBytesRead = 0;
// read file and store in global memory
BOOL bRead = ReadFile(hFile, pvData, dwFileSize, &dwBytesRead, NULL);
_ASSERTE(FALSE != bRead);
GlobalUnlock(hGlobal);
CloseHandle(hFile);
LPSTREAM pstm = NULL;
// create IStream* from global memory
HRESULT hr = CreateStreamOnHGlobal(hGlobal, TRUE, &pstm);
_ASSERTE(SUCCEEDED(hr) && pstm);
// Create IPicture from image file
if (gpPicture)
gpPicture->Release();
hr = ::OleLoadPicture(pstm, dwFileSize, FALSE, IID_IPicture, (LPVOID *)&gpPicture);
_ASSERTE(SUCCEEDED(hr) && gpPicture);
pstm->Release();
InvalidateRect(ghWnd, NULL, TRUE);
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
char buf[64];
i = i%9;
sprintf(buf,"frame%06d.jpg",i+1);
LoadPictureFile(buf);
hdc = BeginPaint(hWnd, &ps);
if (gpPicture)
{
// get width and height of picture
long hmWidth;
long hmHeight;
gpPicture->get_Width(&hmWidth);
gpPicture->get_Height(&hmHeight);
// convert himetric to pixels
int nWidth = MulDiv(hmWidth, GetDeviceCaps(hdc, LOGPIXELSX), HIMETRIC_INCH);
int nHeight = MulDiv(hmHeight, GetDeviceCaps(hdc, LOGPIXELSY), HIMETRIC_INCH);
RECT rc;
GetClientRect(hWnd, &rc);
// display picture using IPicture::Render
gpPicture->Render(hdc, 0, 0, nWidth, nHeight, 0, hmHeight, hmWidth, -hmHeight, &rc);
}
EndPaint(hWnd, &ps);
i = i+1;
return DefWindowProc(hWnd, message, wParam, lParam);
}
2. I don't see any kind of timing. How do you want your frames (images) to be played with the same delay after each other?
3. For me using IPicture::Render doesn't seem to be the fastest way to draw an image.
All in all, why don't you convert your separate files into an AVI stream using the AviFile functions and play this stream?