示例#1
0
        public static (Point TopLeft, Point BottomRight) FindImageBounds([NotNull] Bitmap value, Color backColor, DimensionRestriction restriction = DimensionRestriction.None, int unitWidthLimit = 0, int unitHeightLimit = 0)
        {
            if (value.Width < 2 || value.Height < 2)
            {
                return(Point.Empty, Point.Empty);
            }

            int   width = value.Width, height = value.Height;
            Point topLeft     = new Point();
            Point bottomRight = new Point(width, height);

            unitWidthLimit  = unitWidthLimit.Within(0, width);
            unitHeightLimit = unitHeightLimit.Within(0, height);
            if (unitWidthLimit == width)
            {
                restriction |= DimensionRestriction.KeepWidth;
            }
            if (unitHeightLimit == height)
            {
                restriction |= DimensionRestriction.KeepHeight;
            }

            bool kw = restriction.FastHasFlag(DimensionRestriction.KeepWidth);
            bool kh = restriction.FastHasFlag(DimensionRestriction.KeepHeight);

            if (kw && kh)
            {
                return(topLeft, bottomRight);
            }

            bool kuw   = unitWidthLimit > 0;
            bool kuh   = unitHeightLimit > 0;
            bool found = false;

            if (!kuw || !kuh)
            {
                for (int y = 0; y < height && !found; y++)
                {
                    for (int x = 0; x < width && !found; x++)
                    {
                        Color c = value.GetPixel(x + 1, y + 1);
                        if (c.IsSame(backColor))
                        {
                            continue;
                        }
                        if (!kw && !kuw)
                        {
                            topLeft.X = x;
                        }
                        if (!kh && !kuh)
                        {
                            topLeft.Y = y;
                        }
                        found = true;
                    }
                }

                found = false;
            }

            for (int y = height; y > 0 && !found; y--)
            {
                for (int x = width; x > 0 && !found; x--)
                {
                    Color c = value.GetPixel(x - 1, y - 1);
                    if (c.IsSame(backColor))
                    {
                        continue;
                    }
                    if (!kw)
                    {
                        bottomRight.X = x;
                    }
                    if (!kh)
                    {
                        bottomRight.Y = y;
                    }
                    found = true;
                }
            }

            if (kuw && !kw)
            {
                bottomRight.X = bottomRight.X.Multiplier(unitWidthLimit);
            }
            if (kuh && !kh)
            {
                bottomRight.Y = bottomRight.Y.Multiplier(unitHeightLimit);
            }
            return(topLeft, bottomRight);
        }
示例#2
0
        public static Bitmap Crop([NotNull] Bitmap value, Rectangle rectangle, DimensionRestriction restriction = DimensionRestriction.None)
        {
            // Check source format
            if (!__formatTranslations.TryGetValue(value.PixelFormat, out PixelFormat formatTranslation))
            {
                throw new UnsupportedImageFormatException();
            }
            if (value.Width == 0 || value.Height == 0 || rectangle.IsEmpty)
            {
                return(null);
            }

            int width = value.Width, height = value.Height;

            if (restriction.FastHasFlag(DimensionRestriction.KeepWidth))
            {
                rectangle.X     = 0;
                rectangle.Width = width;
            }

            if (restriction.FastHasFlag(DimensionRestriction.KeepHeight))
            {
                rectangle.Y      = 0;
                rectangle.Height = height;
            }

            if (rectangle.IsEmpty || rectangle.Width <= 0 || rectangle.Height <= 0)
            {
                return(null);
            }
            if (rectangle.X == 0 && rectangle.Y == 0 && rectangle.Width == width && rectangle.Height == height)
            {
                return(Clone(value));
            }
            if (rectangle.X + rectangle.Width > width)
            {
                rectangle.Width = width - rectangle.X;
            }
            if (rectangle.Y + rectangle.Height > height)
            {
                rectangle.Height = height - rectangle.Y;
            }

            BitmapData imageData = value.LockBits(new Rectangle(0, 0, value.Width, value.Height), ImageLockMode.ReadOnly, value.PixelFormat);
            Bitmap     bitmap;

            try
            {
                Size newImageSize = rectangle.Size;
                bitmap = formatTranslation == PixelFormat.Format8bppIndexed
                                                                        ? CreateGreyscaleImage(newImageSize.Width, newImageSize.Height)
                                                                        : new Bitmap(newImageSize.Width, newImageSize.Height, formatTranslation);
                BitmapData bitmapData = bitmap.LockBits(new Rectangle(0, 0, newImageSize.Width, newImageSize.Height), ImageLockMode.ReadWrite, formatTranslation);

                try
                {
                    // Process filter
                    Crop(new UnmanagedImage(imageData), new UnmanagedImage(bitmapData), rectangle);
                }
                finally
                {
                    bitmap.UnlockBits(bitmapData);
                }

                if (value.HorizontalResolution > 0.0)
                {
                    if (value.VerticalResolution > 0.0)
                    {
                        bitmap.SetResolution(value.HorizontalResolution, value.VerticalResolution);
                    }
                }
            }
            finally
            {
                value.UnlockBits(imageData);
            }

            return(bitmap);
        }