Any suggestions for optimizing this code?
I have written a code from the answer given here
My sample code is as follows
void Process(int i)
{
input = (Bitmap)Bitmap.FromFile(@"filepath.bmp");
Bitmap temp = new Bitmap(input.Width, input.Height,
PixelFormat.Format24bppRgb);
Graphics g = Graphics.FromImage(temp);
g.Clear(Color.Red);
g.DrawImage(input, Point.Empty);
temp.Save(stream, ImageFormat.Bmp);
//I need this stream thats further processing
}
void timer_Ex()
{
int i = 11;
for (; ; )
{
if (i == 335) break;
else
{
st.Start();
Process(i);
st.Stop();
Console.WriteLine(st.ElapsedMilliseconds.ToString()开发者_如何学Go);
//This time is more than the time in which thread sleeps
st.Reset();
Thread.Sleep(70);
i++;
}
}
}
So I am trying to convert image from rgb32 to rgb24. But it takes more time on processing than the time in which thread sleeps. Its just a sample code. So just help me with this question "How can i optimize process(int i) to execute in 20 ms or less than 100 ms?"
Things to dramatically improve your code:-
your "input" image is always the same image. But you load it every time Process() is called. Make it a member, and load it once only.
Your "temp" bitmap is allocated every time you call Process(), again it does not need to be. Make it a member, and allocate it once.
You don't dispose of any of your Graphics objects. Bitmaps should be disposed when you are done with them, as should Graphics.
Not really a performance thing, but your for loop is very very odd, and unreadable. Why do you try to reinvent language constructs that are built in? what is wrong with
for (int i=11; i != 335 ; i++)
{
st.Start();
Process(i);
st.Stop();
Console.WriteLine(st.ElapsedMilliseconds.ToString());
//This time is more than the time in which thread sleeps
st.Reset();
Thread.Sleep(70); }
- Graphics goes against COM+. It's slow. Use the Media-namespace that came with WPF.
For the rest of it; it depends. Input size, machine configuration (dx version, graphics card), your skills with C and p/invoke.
Since you are going to make the same size of image the following line can be removed
g.Clear(Color.Red);
It may not make much difference but it can reduce your time
You might want to run it in parallel - whilst each image will still take the same amount of time, you'll be able to process more at once (assuming you have more than 1 core in your CPU)
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