OptimizeBuffer(RasterCodecs,IntPtr,long,ImageOptimizerOptions,ImageOptimizerProgress) Method (original) (raw)
Summary
Optimizes a supported image format buffer using the passed optimization options.
Syntax
Parameters
buffer
The original image buffer in memory as System.IntPtr array. The image format in memory should be one of the following supported formats:
- RasterImageFormat.Jpeg, Bits per pixel: 8 for grayscale, 24 for color.
- RasterImageFormat.Jpeg411, Bits per pixel: 8 for grayscale, 24 for color.
- RasterImageFormat.Jpeg422, Bits per pixel: 8 for grayscale, 24 for color.
- RasterImageFormat.ExifJpeg411, Bits per pixel: 24 (color only).
- RasterImageFormat.ExifJpeg422, Bits per pixel: 24 (color only).
- RasterImageFormat.Gif, Bits per pixel: 1, 2, 3, 4, 5, 6, 7, and 8.
- RasterImageFormat.Png, Bits per pixel: 1, 4, 8, 24, 32, 48, and 64.
- RasterImageFormat.Bmp, Bits per pixel: 1, 4, 8, 16, 24, and 32.
- RasterImageFormat.BmpRle, Bits per pixel: 4, and 8.
length
The size, in bytes, of the buffer parameter in memory.
options
The options used in the optimization process.
progressCallback
Optional callback function that provides information about the progress of the optimization process.
Return Value
A Leadtools.RasterNativeBuffer structure that contains the image optimized buffer in memory.
Example
This example will optimize a Png image file and then save it to a separate folder
using Leadtools;
using Leadtools.Codecs;
using Leadtools.ImageOptimization;
public void TestPngImageOptimizer()
{
// Initialize the RasterCodecs class
RasterCodecs codecs = new RasterCodecs();
// The input and output location
string inputFileName = Path.Combine(LEAD_VARS.ImagesDir, "LittleGFlyingAlpha.png");
string outputFolder = Path.Combine(LEAD_VARS.ImagesDir, "OptimizedImages");
// Initialize a new Optimizer object
ImageOptimizer optimizer = new ImageOptimizer();
// Optimization Options
ImageOptimizerOptions options = ImageOptimizerOptions.Default;
// Set custom optimization options
options.Distance = 20;
options.Percent = 15;
options.PngQualityFactor = 4;
IntPtr bufferPtr;
int bufferSize = 0;
LoadFileIntoPointer(inputFileName, out bufferPtr, out bufferSize);
if (IntPtr.Zero != bufferPtr && bufferSize > 0)
{
RasterNativeBuffer optBuffer = optimizer.OptimizeBuffer(codecs, bufferPtr, bufferSize, options, null);
// Free orgBuffer.PointerBuffer, since it won't be needed anymore.
Marshal.FreeHGlobal(bufferPtr);
// Save this image into the output folder
// Make sure the output folder exists
if (!Directory.Exists(outputFolder))
Directory.CreateDirectory(outputFolder);
// Get the name of the output file from the input file
string outputFileName = Path.Combine(outputFolder, Path.GetFileName(inputFileName));
// Save the optimized buffer to the output file
using (FileStream fs = File.Create(outputFileName))
{
byte[] optArray = new byte[optBuffer.Length];
Marshal.Copy(optBuffer.Data, optArray, 0, optArray.Length);
fs.Write(optArray, 0, optArray.Length);
}
// Free optBuffer.PointerBuffer, since it won't be needed anymore.
Marshal.FreeHGlobal(optBuffer.Data);
// Compare the original image size with the optimized size.
long orgSize = new FileInfo(inputFileName).Length;
long optSize = new FileInfo(outputFileName).Length;
int percentage = (int)((double)optSize * 100.0 / orgSize);
string message = string.Format(
"Original image size: {0} KB{1}Optimized image size: {2} KB{1}Percentage: {3}%",
orgSize / 1024, Environment.NewLine, optSize / 1024,
100 - percentage);
MessageBox.Show(message);
}
//shutdown the RasterCodecs class.
}
// This method opens an image file and loads it into IntPtr.
private void LoadFileIntoPointer(string fileName, out IntPtr ptr, out int size)
{
using (FileStream fs = File.OpenRead(fileName))
{
// Allocate memory to load the file
size = (int)fs.Length;
ptr = Marshal.AllocHGlobal(size);
// Load in 32K chunks
const int bufferSize = 32 * 1024;
byte[] buffer = new byte[bufferSize];
int bytesToRead;
int bytesLeft = (int)fs.Length;
IntPtr tempPtr = ptr; // where we are
do
{
// read a chunk
bytesToRead = Math.Min(bufferSize, bytesLeft);
if (bytesToRead > 0)
{
fs.Read(buffer, 0, bytesToRead);
// copy into our buffer
Marshal.Copy(buffer, 0, tempPtr, bytesToRead);
// move the temp pointer
tempPtr = new IntPtr(tempPtr.ToInt64() + bytesToRead);
bytesLeft -= bytesToRead;
}
}
while (bytesToRead > 0);
}
}
static class LEAD_VARS
{
public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images";
}