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GIF image cropping in c# without add-ons
6
I'm trying to crop gif images in c# without using an add-ons with drawing a rectangle on the image (and I've got it to work with normal image), but .. lets just say the output is less than optimal..
examples:
Origianl Image:
Cropped Image:
and here's the code that I'm using :
public override Image Crop(Rectangle f, bool isStrch, int slashwid, int slashhei)
{
_revert = Image;
GifDecoder();
widmult = Width / (double)slashwid;
heimult = Height / (double)slashhei;
double num = (double)f.X * widmult;
double num2 = (double)f.Y * heimult;
double num3 = (double)f.Width * widmult;
double num4 = (double)f.Height * heimult;
Rectangle srcRect = new Rectangle(isStrch ? ((int)num) : f.X, isStrch ? ((int)num2) : f.Y, isStrch ? ((int)num3) : f.Width, isStrch ? ((int)num4) : f.Height);
CroppedFrames = new Image[Frames.Length];
for (int i = 0; i < Frames.Length; i++)
{
Bitmap image = new Bitmap(Frames[i]);
Bitmap bitmap = new Bitmap(srcRect.Width, srcRect.Height);
using (Graphics graphics = Graphics.FromImage(bitmap))
{
graphics.DrawImage(image, new Rectangle(0, 0, bitmap.Width, bitmap.Height), srcRect, GraphicsUnit.Pixel);
}
CroppedFrames[i] = bitmap;
}
GifEncoder(f.Width,f.Height);
return Image;
}
private void GifDecoder()
{
Stream bitmapStream = new FileStream(Path, FileMode.Open, FileAccess.Read, FileShare.Read);
GifBitmapDecoder gifBitmapDecoder = new GifBitmapDecoder(bitmapStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
Frames = new Image[gifBitmapDecoder.Frames.Count];
for (int i = 0; i < gifBitmapDecoder.Frames.Count; i++)
{
Frames[i] = BitmapFromSource(gifBitmapDecoder.Frames[i]);
}
}
private void GifEncoder(int width,int height)
{
BitmapPalette palette = new BitmapPalette(BitmapImageFromImage(Image),256);
int bytecount = (width * height) / 8;
using (FileStream fs = new FileStream(Path + "output.gif", FileMode.Create))
{
GifBitmapEncoder encoder = new GifBitmapEncoder();
for (int f = 0; f < Frames.Length; f++)
{
byte pixels = imageToByteArray(CroppedFrames[f]);
BitmapSource image = BitmapSource.Create(width,height,96,96,System.Windows.Media.PixelFormats.Indexed8,palette,pixels,width);
encoder.Frames.Add(BitmapFrame.Create(image));
}
encoder.Save(fs);
Image = Image.FromStream(fs);
fs.Close();
}
}
private byte imageToByteArray(Image imageIn)
{
MemoryStream ms = new MemoryStream();
Bitmap aaa = new Bitmap(imageIn);
aaa.Save(ms, ImageFormat.Png);
return ms.ToArray();
}
(bool isStrch, int slashwid, int slashhei) are for checking if the picturebox is smaller than the image or not to get accurate crops with the rect.
c# image image-processing crop gif
asked Nov 20 '18 at 16:21
A LoliA Loli
313
|
show 6 more comments
6
I'm trying to crop gif images in c# without using an add-ons with drawing a rectangle on the image (and I've got it to work with normal image), but .. lets just say the output is less than optimal..
examples:
Origianl Image:
Cropped Image:
and here's the code that I'm using :
public override Image Crop(Rectangle f, bool isStrch, int slashwid, int slashhei)
{
_revert = Image;
GifDecoder();
widmult = Width / (double)slashwid;
heimult = Height / (double)slashhei;
double num = (double)f.X * widmult;
double num2 = (double)f.Y * heimult;
double num3 = (double)f.Width * widmult;
double num4 = (double)f.Height * heimult;
Rectangle srcRect = new Rectangle(isStrch ? ((int)num) : f.X, isStrch ? ((int)num2) : f.Y, isStrch ? ((int)num3) : f.Width, isStrch ? ((int)num4) : f.Height);
CroppedFrames = new Image[Frames.Length];
for (int i = 0; i < Frames.Length; i++)
{
Bitmap image = new Bitmap(Frames[i]);
Bitmap bitmap = new Bitmap(srcRect.Width, srcRect.Height);
using (Graphics graphics = Graphics.FromImage(bitmap))
{
graphics.DrawImage(image, new Rectangle(0, 0, bitmap.Width, bitmap.Height), srcRect, GraphicsUnit.Pixel);
}
CroppedFrames[i] = bitmap;
}
GifEncoder(f.Width,f.Height);
return Image;
}
private void GifDecoder()
{
Stream bitmapStream = new FileStream(Path, FileMode.Open, FileAccess.Read, FileShare.Read);
GifBitmapDecoder gifBitmapDecoder = new GifBitmapDecoder(bitmapStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
Frames = new Image[gifBitmapDecoder.Frames.Count];
for (int i = 0; i < gifBitmapDecoder.Frames.Count; i++)
{
Frames[i] = BitmapFromSource(gifBitmapDecoder.Frames[i]);
}
}
private void GifEncoder(int width,int height)
{
BitmapPalette palette = new BitmapPalette(BitmapImageFromImage(Image),256);
int bytecount = (width * height) / 8;
using (FileStream fs = new FileStream(Path + "output.gif", FileMode.Create))
{
GifBitmapEncoder encoder = new GifBitmapEncoder();
for (int f = 0; f < Frames.Length; f++)
{
byte pixels = imageToByteArray(CroppedFrames[f]);
BitmapSource image = BitmapSource.Create(width,height,96,96,System.Windows.Media.PixelFormats.Indexed8,palette,pixels,width);
encoder.Frames.Add(BitmapFrame.Create(image));
}
encoder.Save(fs);
Image = Image.FromStream(fs);
fs.Close();
}
}
private byte imageToByteArray(Image imageIn)
{
MemoryStream ms = new MemoryStream();
Bitmap aaa = new Bitmap(imageIn);
aaa.Save(ms, ImageFormat.Png);
return ms.ToArray();
}
(bool isStrch, int slashwid, int slashhei) are for checking if the picturebox is smaller than the image or not to get accurate crops with the rect.
c# image image-processing crop gif
asked Nov 20 '18 at 16:21
A LoliA Loli
313
I do not speak C#,but my best bet here is that you are missing the alpha channel. Note how the original gif has transparency but your output has no information about that. By not getting RGBA, and instead reading as RGB, you are reading random data thus looks crap.
– Ander Biguri
Nov 21 '18 at 11:14
@AnderBiguri i actually managed to get it working but, it still doesn't loop
– A Loli
Nov 21 '18 at 17:22
So... you did not manage to get it working?
– Ander Biguri
Nov 21 '18 at 17:33
at this point yes, but it still doesn't loop, anyway this isn't my question anyway so this should be closed
– A Loli
Nov 22 '18 at 18:38
1
@AnderBiguri Yes. Gif format has a specific system where one colour index gets indicated as being "the transparent colour", and all pixels of that value are treated as transparent. In fact, there are more formats like that; png even supports alpha values for all of its palette indices, but .Net is equally dumb about that format and also treats it as ARGB.
– Nyerguds
Nov 28 '18 at 22:10
|
show 6 more comments
6
6
6
I'm trying to crop gif images in c# without using an add-ons with drawing a rectangle on the image (and I've got it to work with normal image), but .. lets just say the output is less than optimal..
examples:
Origianl Image:
Cropped Image:
and here's the code that I'm using :
public override Image Crop(Rectangle f, bool isStrch, int slashwid, int slashhei)
{
_revert = Image;
GifDecoder();
widmult = Width / (double)slashwid;
heimult = Height / (double)slashhei;
double num = (double)f.X * widmult;
double num2 = (double)f.Y * heimult;
double num3 = (double)f.Width * widmult;
double num4 = (double)f.Height * heimult;
Rectangle srcRect = new Rectangle(isStrch ? ((int)num) : f.X, isStrch ? ((int)num2) : f.Y, isStrch ? ((int)num3) : f.Width, isStrch ? ((int)num4) : f.Height);
CroppedFrames = new Image[Frames.Length];
for (int i = 0; i < Frames.Length; i++)
{
Bitmap image = new Bitmap(Frames[i]);
Bitmap bitmap = new Bitmap(srcRect.Width, srcRect.Height);
using (Graphics graphics = Graphics.FromImage(bitmap))
{
graphics.DrawImage(image, new Rectangle(0, 0, bitmap.Width, bitmap.Height), srcRect, GraphicsUnit.Pixel);
}
CroppedFrames[i] = bitmap;
}
GifEncoder(f.Width,f.Height);
return Image;
}
private void GifDecoder()
{
Stream bitmapStream = new FileStream(Path, FileMode.Open, FileAccess.Read, FileShare.Read);
GifBitmapDecoder gifBitmapDecoder = new GifBitmapDecoder(bitmapStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
Frames = new Image[gifBitmapDecoder.Frames.Count];
for (int i = 0; i < gifBitmapDecoder.Frames.Count; i++)
{
Frames[i] = BitmapFromSource(gifBitmapDecoder.Frames[i]);
}
}
private void GifEncoder(int width,int height)
{
BitmapPalette palette = new BitmapPalette(BitmapImageFromImage(Image),256);
int bytecount = (width * height) / 8;
using (FileStream fs = new FileStream(Path + "output.gif", FileMode.Create))
{
GifBitmapEncoder encoder = new GifBitmapEncoder();
for (int f = 0; f < Frames.Length; f++)
{
byte pixels = imageToByteArray(CroppedFrames[f]);
BitmapSource image = BitmapSource.Create(width,height,96,96,System.Windows.Media.PixelFormats.Indexed8,palette,pixels,width);
encoder.Frames.Add(BitmapFrame.Create(image));
}
encoder.Save(fs);
Image = Image.FromStream(fs);
fs.Close();
}
}
private byte imageToByteArray(Image imageIn)
{
MemoryStream ms = new MemoryStream();
Bitmap aaa = new Bitmap(imageIn);
aaa.Save(ms, ImageFormat.Png);
return ms.ToArray();
}
(bool isStrch, int slashwid, int slashhei) are for checking if the picturebox is smaller than the image or not to get accurate crops with the rect.
c# image image-processing crop gif
asked Nov 20 '18 at 16:21
A LoliA Loli
313
I'm trying to crop gif images in c# without using an add-ons with drawing a rectangle on the image (and I've got it to work with normal image), but .. lets just say the output is less than optimal..
examples:
Origianl Image:
Cropped Image:
and here's the code that I'm using :
public override Image Crop(Rectangle f, bool isStrch, int slashwid, int slashhei)
{
_revert = Image;
GifDecoder();
widmult = Width / (double)slashwid;
heimult = Height / (double)slashhei;
double num = (double)f.X * widmult;
double num2 = (double)f.Y * heimult;
double num3 = (double)f.Width * widmult;
double num4 = (double)f.Height * heimult;
Rectangle srcRect = new Rectangle(isStrch ? ((int)num) : f.X, isStrch ? ((int)num2) : f.Y, isStrch ? ((int)num3) : f.Width, isStrch ? ((int)num4) : f.Height);
CroppedFrames = new Image[Frames.Length];
for (int i = 0; i < Frames.Length; i++)
{
Bitmap image = new Bitmap(Frames[i]);
Bitmap bitmap = new Bitmap(srcRect.Width, srcRect.Height);
using (Graphics graphics = Graphics.FromImage(bitmap))
{
graphics.DrawImage(image, new Rectangle(0, 0, bitmap.Width, bitmap.Height), srcRect, GraphicsUnit.Pixel);
}
CroppedFrames[i] = bitmap;
}
GifEncoder(f.Width,f.Height);
return Image;
}
private void GifDecoder()
{
Stream bitmapStream = new FileStream(Path, FileMode.Open, FileAccess.Read, FileShare.Read);
GifBitmapDecoder gifBitmapDecoder = new GifBitmapDecoder(bitmapStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
Frames = new Image[gifBitmapDecoder.Frames.Count];
for (int i = 0; i < gifBitmapDecoder.Frames.Count; i++)
{
Frames[i] = BitmapFromSource(gifBitmapDecoder.Frames[i]);
}
}
private void GifEncoder(int width,int height)
{
BitmapPalette palette = new BitmapPalette(BitmapImageFromImage(Image),256);
int bytecount = (width * height) / 8;
using (FileStream fs = new FileStream(Path + "output.gif", FileMode.Create))
{
GifBitmapEncoder encoder = new GifBitmapEncoder();
for (int f = 0; f < Frames.Length; f++)
{
byte pixels = imageToByteArray(CroppedFrames[f]);
BitmapSource image = BitmapSource.Create(width,height,96,96,System.Windows.Media.PixelFormats.Indexed8,palette,pixels,width);
encoder.Frames.Add(BitmapFrame.Create(image));
}
encoder.Save(fs);
Image = Image.FromStream(fs);
fs.Close();
}
}
private byte imageToByteArray(Image imageIn)
{
MemoryStream ms = new MemoryStream();
Bitmap aaa = new Bitmap(imageIn);
aaa.Save(ms, ImageFormat.Png);
return ms.ToArray();
}
(bool isStrch, int slashwid, int slashhei) are for checking if the picturebox is smaller than the image or not to get accurate crops with the rect.
c# image image-processing crop gif
c# image image-processing crop gif
asked Nov 20 '18 at 16:21
A LoliA Loli
313
asked Nov 20 '18 at 16:21
A LoliA Loli
313
edited Nov 20 '18 at 18:12
A Loli
asked Nov 20 '18 at 16:21
A LoliA Loli
313
asked Nov 20 '18 at 16:21
A LoliA Loli
313
asked Nov 20 '18 at 16:21
A LoliA Loli
313
313
I do not speak C#,but my best bet here is that you are missing the alpha channel. Note how the original gif has transparency but your output has no information about that. By not getting RGBA, and instead reading as RGB, you are reading random data thus looks crap.
– Ander Biguri
Nov 21 '18 at 11:14
@AnderBiguri i actually managed to get it working but, it still doesn't loop
– A Loli
Nov 21 '18 at 17:22
So... you did not manage to get it working?
– Ander Biguri
Nov 21 '18 at 17:33
at this point yes, but it still doesn't loop, anyway this isn't my question anyway so this should be closed
– A Loli
Nov 22 '18 at 18:38
1
@AnderBiguri Yes. Gif format has a specific system where one colour index gets indicated as being "the transparent colour", and all pixels of that value are treated as transparent. In fact, there are more formats like that; png even supports alpha values for all of its palette indices, but .Net is equally dumb about that format and also treats it as ARGB.
– Nyerguds
Nov 28 '18 at 22:10
|
show 6 more comments
I do not speak C#,but my best bet here is that you are missing the alpha channel. Note how the original gif has transparency but your output has no information about that. By not getting RGBA, and instead reading as RGB, you are reading random data thus looks crap.
– Ander Biguri
Nov 21 '18 at 11:14
@AnderBiguri i actually managed to get it working but, it still doesn't loop
– A Loli
Nov 21 '18 at 17:22
So... you did not manage to get it working?
– Ander Biguri
Nov 21 '18 at 17:33
at this point yes, but it still doesn't loop, anyway this isn't my question anyway so this should be closed
– A Loli
Nov 22 '18 at 18:38
1
@AnderBiguri Yes. Gif format has a specific system where one colour index gets indicated as being "the transparent colour", and all pixels of that value are treated as transparent. In fact, there are more formats like that; png even supports alpha values for all of its palette indices, but .Net is equally dumb about that format and also treats it as ARGB.
– Nyerguds
Nov 28 '18 at 22:10
I do not speak C#,but my best bet here is that you are missing the alpha channel. Note how the original gif has transparency but your output has no information about that. By not getting RGBA, and instead reading as RGB, you are reading random data thus looks crap.
– Ander Biguri
Nov 21 '18 at 11:14
I do not speak C#,but my best bet here is that you are missing the alpha channel. Note how the original gif has transparency but your output has no information about that. By not getting RGBA, and instead reading as RGB, you are reading random data thus looks crap.
– Ander Biguri
Nov 21 '18 at 11:14
@AnderBiguri i actually managed to get it working but, it still doesn't loop
– A Loli
Nov 21 '18 at 17:22
@AnderBiguri i actually managed to get it working but, it still doesn't loop
– A Loli
Nov 21 '18 at 17:22
So... you did not manage to get it working?
– Ander Biguri
Nov 21 '18 at 17:33
So... you did not manage to get it working?
– Ander Biguri
Nov 21 '18 at 17:33
at this point yes, but it still doesn't loop, anyway this isn't my question anyway so this should be closed
– A Loli
Nov 22 '18 at 18:38
at this point yes, but it still doesn't loop, anyway this isn't my question anyway so this should be closed
– A Loli
Nov 22 '18 at 18:38
1
1
@AnderBiguri Yes. Gif format has a specific system where one colour index gets indicated as being "the transparent colour", and all pixels of that value are treated as transparent. In fact, there are more formats like that; png even supports alpha values for all of its palette indices, but .Net is equally dumb about that format and also treats it as ARGB.
– Nyerguds
Nov 28 '18 at 22:10
@AnderBiguri Yes. Gif format has a specific system where one colour index gets indicated as being "the transparent colour", and all pixels of that value are treated as transparent. In fact, there are more formats like that; png even supports alpha values for all of its palette indices, but .Net is equally dumb about that format and also treats it as ARGB.
– Nyerguds
Nov 28 '18 at 22:10
|
show 6 more comments
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I do not speak C#,but my best bet here is that you are missing the alpha channel. Note how the original gif has transparency but your output has no information about that. By not getting RGBA, and instead reading as RGB, you are reading random data thus looks crap.
– Ander Biguri
Nov 21 '18 at 11:14
@AnderBiguri i actually managed to get it working but, it still doesn't loop
– A Loli
Nov 21 '18 at 17:22
So... you did not manage to get it working?
– Ander Biguri
Nov 21 '18 at 17:33
at this point yes, but it still doesn't loop, anyway this isn't my question anyway so this should be closed
– A Loli
Nov 22 '18 at 18:38
1
@AnderBiguri Yes. Gif format has a specific system where one colour index gets indicated as being "the transparent colour", and all pixels of that value are treated as transparent. In fact, there are more formats like that; png even supports alpha values for all of its palette indices, but .Net is equally dumb about that format and also treats it as ARGB.
– Nyerguds
Nov 28 '18 at 22:10