File: mono\System.Drawing.Imaging\GifCodecTests.cs
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Project: src\src\System.Drawing.Common\tests\System.Drawing.Common.Tests.csproj (System.Drawing.Common.Tests)
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
// GIF Codec class testing unit
//
// Authors:
//  Jordi Mas i Hernandez (jordi@ximian.com)
//  Sebastien Pouliot  <sebastien@ximian.com>
//
// Copyright (C) 2006, 2007 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
 
using System.Drawing.Imaging;
 
namespace MonoTests.System.Drawing.Imaging;
 
public class GifCodecTest
{
    /* Checks bitmap features on a known 1bbp bitmap */
    private static void Bitmap8bitsFeatures(string filename)
    {
        using Bitmap bmp = new(filename);
        GraphicsUnit unit = GraphicsUnit.World;
        RectangleF rect = bmp.GetBounds(ref unit);
 
        Assert.Equal(PixelFormat.Format8bppIndexed, bmp.PixelFormat);
        Assert.Equal(110, bmp.Width);
        Assert.Equal(100, bmp.Height);
 
        Assert.Equal(0, rect.X);
        Assert.Equal(0, rect.Y);
        Assert.Equal(110, rect.Width);
        Assert.Equal(100, rect.Height);
 
        Assert.Equal(110, bmp.Size.Width);
        Assert.Equal(100, bmp.Size.Height);
    }
 
    [Fact]
    public void Bitmap8bitsFeatures_Gif89()
    {
        Bitmap8bitsFeatures(Helpers.GetTestBitmapPath("nature24bits.gif"));
    }
 
    [Fact]
    public void Bitmap8bitsFeatures_Gif87()
    {
        Bitmap8bitsFeatures(Helpers.GetTestBitmapPath("nature24bits87.gif"));
    }
 
    private static void Bitmap8bitsPixels(string filename)
    {
        using Bitmap bmp = new(filename);
        // sampling values from a well known bitmap
        Assert.Equal(-10644802, bmp.GetPixel(0, 0).ToArgb());
        Assert.Equal(-12630705, bmp.GetPixel(0, 32).ToArgb());
        Assert.Equal(-14537409, bmp.GetPixel(0, 64).ToArgb());
        Assert.Equal(-14672099, bmp.GetPixel(0, 96).ToArgb());
        Assert.Equal(-526863, bmp.GetPixel(32, 0).ToArgb());
        Assert.Equal(-10263970, bmp.GetPixel(32, 32).ToArgb());
        Assert.Equal(-10461317, bmp.GetPixel(32, 64).ToArgb());
        Assert.Equal(-9722415, bmp.GetPixel(32, 96).ToArgb());
        Assert.Equal(-131076, bmp.GetPixel(64, 0).ToArgb());
        Assert.Equal(-2702435, bmp.GetPixel(64, 32).ToArgb());
        Assert.Equal(-6325922, bmp.GetPixel(64, 64).ToArgb());
        Assert.Equal(-12411924, bmp.GetPixel(64, 96).ToArgb());
        Assert.Equal(-131076, bmp.GetPixel(96, 0).ToArgb());
        Assert.Equal(-7766649, bmp.GetPixel(96, 32).ToArgb());
        Assert.Equal(-11512986, bmp.GetPixel(96, 64).ToArgb());
        Assert.Equal(-12616230, bmp.GetPixel(96, 96).ToArgb());
    }
 
    [Fact]
    public void Bitmap8bitsPixels_Gif89()
    {
        Bitmap8bitsPixels(Helpers.GetTestBitmapPath("nature24bits.gif"));
    }
 
    [Fact]
    public void Bitmap8bitsPixels_Gif87()
    {
        Bitmap8bitsPixels(Helpers.GetTestBitmapPath("nature24bits87.gif"));
    }
 
    [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsNotArm64Process))] // [ActiveIssue("https://github.com/dotnet/winforms/issues/8817")]
    public void Bitmap8bitsData()
    {
        string sInFile = Helpers.GetTestBitmapPath("nature24bits.gif");
        using Bitmap bmp = new(sInFile);
        BitmapData data = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
        try
        {
            Assert.Equal(bmp.Height, data.Height);
            Assert.Equal(bmp.Width, data.Width);
            Assert.Equal(PixelFormat.Format24bppRgb, data.PixelFormat);
            Assert.Equal(332, data.Stride);
            Assert.Equal(100, data.Height);
 
            unsafe
            {
                byte* scan = (byte*)data.Scan0;
                // sampling values from a well known bitmap
                Assert.Equal(190, *(scan + 0));
                Assert.Equal(217, *(scan + 1009));
                Assert.Equal(120, *(scan + 2018));
                Assert.Equal(253, *(scan + 3027));
                Assert.Equal(233, *(scan + 4036));
                Assert.Equal(176, *(scan + 5045));
                Assert.Equal(151, *(scan + 6054));
                Assert.Equal(220, *(scan + 7063));
                Assert.Equal(139, *(scan + 8072));
                Assert.Equal(121, *(scan + 9081));
                Assert.Equal(160, *(scan + 10090));
                Assert.Equal(92, *(scan + 11099));
                Assert.Equal(96, *(scan + 12108));
                Assert.Equal(64, *(scan + 13117));
                Assert.Equal(156, *(scan + 14126));
                Assert.Equal(68, *(scan + 15135));
                Assert.Equal(156, *(scan + 16144));
                Assert.Equal(84, *(scan + 17153));
                Assert.Equal(55, *(scan + 18162));
                Assert.Equal(68, *(scan + 19171));
                Assert.Equal(116, *(scan + 20180));
                Assert.Equal(61, *(scan + 21189));
                Assert.Equal(69, *(scan + 22198));
                Assert.Equal(75, *(scan + 23207));
                Assert.Equal(61, *(scan + 24216));
                Assert.Equal(66, *(scan + 25225));
                Assert.Equal(40, *(scan + 26234));
                Assert.Equal(55, *(scan + 27243));
                Assert.Equal(53, *(scan + 28252));
                Assert.Equal(215, *(scan + 29261));
                Assert.Equal(99, *(scan + 30270));
                Assert.Equal(67, *(scan + 31279));
                Assert.Equal(142, *(scan + 32288));
            }
        }
        finally
        {
            bmp.UnlockBits(data);
        }
    }
 
    [Fact]
    public void Interlaced()
    {
        string sInFile = Helpers.GetTestBitmapPath("81773-interlaced.gif");
        using Bitmap bmp = new(sInFile);
        for (int i = 0; i < 255; i++)
        {
            Color c = bmp.GetPixel(0, i);
            Assert.Equal(255, c.A);
            Assert.Equal(i, c.R);
            Assert.Equal(i, c.G);
            Assert.Equal(i, c.B);
        }
    }
 
    private static void Save(PixelFormat original, PixelFormat expected, bool exactColorCheck)
    {
        string sOutFile = $"linerect-{expected}.gif";
 
        // Save
        Bitmap bmp = new(100, 100, original);
        Graphics gr = Graphics.FromImage(bmp);
 
        using (Pen p = new(Color.Red, 2))
        {
            gr.DrawLine(p, 10.0F, 10.0F, 90.0F, 90.0F);
            gr.DrawRectangle(p, 10.0F, 10.0F, 80.0F, 80.0F);
        }
 
        try
        {
            bmp.Save(sOutFile, ImageFormat.Gif);
 
            // Load
            using Bitmap bmpLoad = new(sOutFile);
            Assert.Equal(expected, bmpLoad.PixelFormat);
            Color color = bmpLoad.GetPixel(10, 10);
            if (exactColorCheck)
            {
                Assert.Equal(Color.FromArgb(255, 255, 0, 0), color);
            }
            else
            {
                // FIXME: we don't save a pure red (F8 instead of FF) into the file so the color-check assert will fail
                // this is due to libgif's QuantizeBuffer. An alternative would be to make our own that checks if less than 256 colors
                // are used in the bitmap (or else use QuantizeBuffer).
                Assert.Equal(255, color.A);
                Assert.True(color.R >= 248);
                Assert.Equal(0, color.G);
                Assert.Equal(0, color.B);
            }
        }
        finally
        {
            gr.Dispose();
            bmp.Dispose();
            try
            {
                File.Delete(sOutFile);
            }
            catch
            {
            }
        }
    }
 
    [Fact]
    public void Save_24bppRgb()
    {
        Save(PixelFormat.Format24bppRgb, PixelFormat.Format8bppIndexed, false);
    }
 
    [Fact]
    public void Save_32bppRgb()
    {
        Save(PixelFormat.Format32bppRgb, PixelFormat.Format8bppIndexed, false);
    }
 
    [Fact]
    public void Save_32bppArgb()
    {
        Save(PixelFormat.Format32bppArgb, PixelFormat.Format8bppIndexed, false);
    }
 
    [Fact]
    public void Save_32bppPArgb()
    {
        Save(PixelFormat.Format32bppPArgb, PixelFormat.Format8bppIndexed, false);
    }
}