Basic video fade support.

1 files changed, 107 insertions, 0 deletions

diff --git a/src/lib/image.cc b/src/lib/image.cc
index 0b06d39b1..0da2d1e48 100644
--- a/src/lib/image.cc
+++ b/src/lib/image.cc
@@ -717,3 +717,110 @@ operator== (Image const & a, Image const & b)
 
 	return true;
 }
+
+void
+Image::fade (float f)
+{
+	switch (_pixel_format) {
+	case PIX_FMT_YUV420P:
+	case PIX_FMT_YUV422P:
+	case PIX_FMT_YUV444P:
+	case PIX_FMT_YUV411P:
+	case PIX_FMT_YUVJ420P:
+	case PIX_FMT_YUVJ422P:
+	case PIX_FMT_YUVJ444P:
+	case PIX_FMT_RGB24:
+	case PIX_FMT_ARGB:
+	case PIX_FMT_RGBA:
+	case PIX_FMT_ABGR:
+	case PIX_FMT_BGRA:
+	case PIX_FMT_RGB555LE:
+		/* 8-bit */
+		for (int c = 0; c < 3; ++c) {
+			uint8_t* p = data()[c];
+			for (int y = 0; y < lines(c); ++y) {
+				uint8_t* q = p;
+				for (int x = 0; x < line_size()[c]; ++x) {
+					*q = int (float (*q) * f);
+					++q;
+				}
+				p += stride()[c];
+			}
+		}
+		break;
+
+	case PIX_FMT_YUV422P9LE:
+	case PIX_FMT_YUV444P9LE:
+	case PIX_FMT_YUV422P10LE:
+	case PIX_FMT_YUV444P10LE:
+	case PIX_FMT_YUV422P16LE:
+	case PIX_FMT_YUV444P16LE:
+	case AV_PIX_FMT_YUVA420P9LE:
+	case AV_PIX_FMT_YUVA422P9LE:
+	case AV_PIX_FMT_YUVA444P9LE:
+	case AV_PIX_FMT_YUVA420P10LE:
+	case AV_PIX_FMT_YUVA422P10LE:
+	case AV_PIX_FMT_YUVA444P10LE:
+		/* 16-bit little-endian */
+		for (int c = 0; c < 3; ++c) {
+			int const stride_pixels = stride()[c] / 2;
+			int const line_size_pixels = line_size()[c] / 2;
+			uint16_t* p = reinterpret_cast<uint16_t*> (data()[c]);
+			for (int y = 0; y < lines(c); ++y) {
+				uint16_t* q = p;
+				for (int x = 0; x < line_size_pixels; ++x) {
+					*q = int (float (*q) * f);
+					++q;
+				}
+				p += stride_pixels;
+			}
+		}
+		break;
+
+	case PIX_FMT_YUV422P9BE:
+	case PIX_FMT_YUV444P9BE:
+	case PIX_FMT_YUV444P10BE:
+	case PIX_FMT_YUV422P10BE:
+	case AV_PIX_FMT_YUVA420P9BE:
+	case AV_PIX_FMT_YUVA422P9BE:
+	case AV_PIX_FMT_YUVA444P9BE:
+	case AV_PIX_FMT_YUVA420P10BE:
+	case AV_PIX_FMT_YUVA422P10BE:
+	case AV_PIX_FMT_YUVA444P10BE:
+	case AV_PIX_FMT_YUVA420P16BE:
+	case AV_PIX_FMT_YUVA422P16BE:
+	case AV_PIX_FMT_YUVA444P16BE:
+		/* 16-bit big-endian */
+		for (int c = 0; c < 3; ++c) {
+			int const stride_pixels = stride()[c] / 2;
+			int const line_size_pixels = line_size()[c] / 2;
+			uint16_t* p = reinterpret_cast<uint16_t*> (data()[c]);
+			for (int y = 0; y < lines(c); ++y) {
+				uint16_t* q = p;
+				for (int x = 0; x < line_size_pixels; ++x) {
+					*q = swap_16 (int (float (swap_16 (*q)) * f));
+					++q;
+				}
+				p += stride_pixels;
+			}
+		}
+		break;
+
+	case PIX_FMT_UYVY422:
+	{
+		int const Y = lines(0);
+		int const X = line_size()[0];
+		uint8_t* p = data()[0];
+		for (int y = 0; y < Y; ++y) {
+			for (int x = 0; x < X; ++x) {
+				*p = int (float (*p) * f);
+				++p;
+			}
+		}
+		break;
+	}
+
+	default:
+		throw PixelFormatError ("fade()", _pixel_format);
+	}
+}