Fix scaling functions (#385 )

This commit corrects two small errors that causes the improper results reported in #312. - A copy paste typo (most likely) which sets the Dy component of the image rectangle to Dx. - The tmp array in fastBoxSampling was not properly reset because the last argument in memset should be the number of bytes to fill in and not the number of elements.
Update golang.org/x/image commit hash to 723b81c (#370 )
2025-09-27 12:52:20 +08:00 · 2022-03-18 15:04:36 +09:00 · 2022-03-17 16:09:36 +09:00 · 2022-03-14 10:34:25 -04:00 · 2022-03-14 10:34:10 -04:00 · 2022-03-08 03:09:01 -06:00
11 changed files with 408 additions and 25 deletions
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -17,9 +17,9 @@ jobs:
    name: Linux Go ${{ matrix.go }}
    steps:
      - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
      - name: Setup Go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v3
        with:
          go-version: ${{ matrix.go }}
      - name: Install dependencies
@@ -43,9 +43,9 @@ jobs:
    name: Darwin Go ${{ matrix.go }}
    steps:
      - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
      - name: Setup Go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v3
        with:
          go-version: ${{ matrix.go }}
      - name: Install dependencies
@@ -62,9 +62,9 @@ jobs:
    name: Check Licenses
    steps:
      - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
      - name: Setup Go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v3
        with:
          go-version: '1.16'
      - name: Installing go-licenses
--- a/.github/workflows/renovate-go-mod-fix.yaml
+++ b/.github/workflows/renovate-go-mod-fix.yaml
@@ -9,7 +9,7 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
        with:
          fetch-depth: 2
      - name: fix
--- a/go.mod
+++ b/go.mod
@@ -10,6 +10,6 @@ require (
 	github.com/pion/logging v0.2.2
 	github.com/pion/rtp v1.7.4
 	github.com/pion/webrtc/v3 v3.1.10
-	golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d
+	golang.org/x/image v0.0.0-20220302094943-723b81ca9867
 	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
 )
--- a/go.sum
+++ b/go.sum
@@ -100,8 +100,8 @@ golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20210322153248-0c34fe9e7dc2/go.mod h1:T9bdIzuCu7OtxOm1hfPfRQxPLYneinmdGuTeoZ9dtd4=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519 h1:7I4JAnoQBe7ZtJcBaYHi5UtiO8tQHbUSXxL+pnGRANg=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d h1:RNPAfi2nHY7C2srAV8A49jpsYr0ADedCk1wq6fTMTvs=
-golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d/go.mod h1:023OzeP/+EPmXeapQh35lcL3II3LrY8Ic+EFFKVhULM=
+golang.org/x/image v0.0.0-20220302094943-723b81ca9867 h1:TcHcE0vrmgzNH1v3ppjcMGbhG5+9fMuvOmUYwNEF4q4=
+golang.org/x/image v0.0.0-20220302094943-723b81ca9867/go.mod h1:023OzeP/+EPmXeapQh35lcL3II3LrY8Ic+EFFKVhULM=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
--- a/pkg/codec/openh264/bridge.cpp
+++ b/pkg/codec/openh264/bridge.cpp
@@ -88,9 +88,8 @@ Slice enc_encode(Encoder *e, Frame f, int *eresult) {
  pic.iPicWidth = f.width;
  pic.iPicHeight = f.height;
  pic.iColorFormat = videoFormatI420;
-  // We always received I420 format
-  pic.iStride[0] = pic.iPicWidth;
-  pic.iStride[1] = pic.iStride[2] = pic.iPicWidth / 2;
+  pic.iStride[0] = f.ystride;
+  pic.iStride[1] = pic.iStride[2] = f.cstride;
  pic.pData[0] = (unsigned char *)f.y;
  pic.pData[1] = (unsigned char *)f.u;
  pic.pData[2] = (unsigned char *)f.v;
--- a/pkg/codec/openh264/bridge.hpp
+++ b/pkg/codec/openh264/bridge.hpp
@@ -12,6 +12,8 @@ typedef struct Slice {

 typedef struct Frame {
  void *y, *u, *v;
+  int ystride;
+  int cstride;
  int height;
  int width;
 } Frame;
--- a/pkg/codec/openh264/openh264.go
+++ b/pkg/codec/openh264/openh264.go
@@ -65,11 +65,13 @@ func (e *encoder) Read() ([]byte, func(), error) {
 	bounds := yuvImg.Bounds()
 	var rv C.int
 	s := C.enc_encode(e.engine, C.Frame{
-		y:      unsafe.Pointer(&yuvImg.Y[0]),
-		u:      unsafe.Pointer(&yuvImg.Cb[0]),
-		v:      unsafe.Pointer(&yuvImg.Cr[0]),
-		height: C.int(bounds.Max.Y - bounds.Min.Y),
-		width:  C.int(bounds.Max.X - bounds.Min.X),
+		y:       unsafe.Pointer(&yuvImg.Y[0]),
+		u:       unsafe.Pointer(&yuvImg.Cb[0]),
+		v:       unsafe.Pointer(&yuvImg.Cr[0]),
+		ystride: C.int(yuvImg.YStride),
+		cstride: C.int(yuvImg.CStride),
+		height:  C.int(bounds.Max.Y - bounds.Min.Y),
+		width:   C.int(bounds.Max.X - bounds.Min.X),
 	}, &rv)
 	if err := errResult(rv); err != nil {
 		return nil, func() {}, fmt.Errorf("failed in encoding: %v", err)
--- a/pkg/io/video/scale.go
+++ b/pkg/io/video/scale.go
@@ -109,7 +109,7 @@ func Scale(width, height int, scaler Scaler) TransformFunc {
 			yDy := rect.Dy()
 			cRect := fixedRect(rect, i1.SubsampleRatio)
 			cDx := cRect.Dx()
-			cDy := cRect.Dx()
+			cDy := cRect.Dy()
 			yLen := yDx * yDy
 			cLen := cDx * cDy
 			if len(imgDst.Y) < yLen {
--- a/pkg/io/video/scale_test.go
+++ b/pkg/io/video/scale_test.go
@@ -36,6 +36,32 @@ func TestScale(t *testing.T) {
 				Rect:   image.Rect(0, 0, 2, 2),
 			},
 		},
+		"RGBASameSize": {
+			src: &image.RGBA{
+				Pix: []uint8{
+					// R     G     B     A |   R     G     B     A |   R     G     B     A |   R     G     B     A
+					0x80, 0x00, 0x00, 0xFF, 0x80, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF,
+					0x80, 0x00, 0x00, 0xFF, 0x80, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF,
+					0x00, 0x40, 0x00, 0xFF, 0x00, 0x40, 0x00, 0xFF, 0x00, 0x00, 0x60, 0xFF, 0x00, 0x00, 0x60, 0xFF,
+					0x00, 0x40, 0x00, 0xFF, 0x00, 0x40, 0x00, 0xFF, 0x00, 0x00, 0x60, 0xFF, 0x00, 0x00, 0x60, 0xFF,
+				},
+				Stride: 16,
+				Rect:   image.Rect(0, 0, 4, 4),
+			},
+			width:  4,
+			height: 4,
+			expected: &image.RGBA{
+				Pix: []uint8{
+					// R     G     B     A |   R     G     B     A |   R     G     B     A |   R     G     B     A
+					0x80, 0x00, 0x00, 0xFF, 0x80, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF,
+					0x80, 0x00, 0x00, 0xFF, 0x80, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF,
+					0x00, 0x40, 0x00, 0xFF, 0x00, 0x40, 0x00, 0xFF, 0x00, 0x00, 0x60, 0xFF, 0x00, 0x00, 0x60, 0xFF,
+					0x00, 0x40, 0x00, 0xFF, 0x00, 0x40, 0x00, 0xFF, 0x00, 0x00, 0x60, 0xFF, 0x00, 0x00, 0x60, 0xFF,
+				},
+				Stride: 16,
+				Rect:   image.Rect(0, 0, 4, 4),
+			},
+		},
 		"I444": {
 			src: &image.YCbCr{
 				SubsampleRatio: image.YCbCrSubsampleRatio444,
@@ -91,6 +117,70 @@ func TestScale(t *testing.T) {
 				Rect:    image.Rect(0, 0, 3, 3),
 			},
 		},
+		"I444SameSize": {
+			src: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio444,
+				Y: []uint8{
+					0xF0, 0xF0, 0x00, 0x00, 0x00, 0x00,
+					0xF0, 0xF0, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40,
+					0x00, 0x00, 0x80, 0x80, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x00, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x20, 0x80, 0x80, 0x80, 0x80,
+					0x20, 0x20, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80, 0xC0, 0xC0,
+					0x80, 0x80, 0x80, 0x80, 0xC0, 0xC0,
+					0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+				},
+				Cr: []uint8{
+					0xE0, 0xE0, 0x80, 0x80, 0x80, 0x80,
+					0xE0, 0xE0, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x40, 0x40, 0x80, 0x80,
+					0x80, 0x80, 0x40, 0x40, 0x80, 0x80,
+				},
+				YStride: 6,
+				CStride: 6,
+				Rect:    image.Rect(0, 0, 6, 6),
+			},
+			width:  6,
+			height: 6,
+			expected: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio444,
+				Y: []uint8{
+					0xF0, 0xF0, 0x00, 0x00, 0x00, 0x00,
+					0xF0, 0xF0, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40,
+					0x00, 0x00, 0x80, 0x80, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x00, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x20, 0x80, 0x80, 0x80, 0x80,
+					0x20, 0x20, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80, 0xC0, 0xC0,
+					0x80, 0x80, 0x80, 0x80, 0xC0, 0xC0,
+					0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+				},
+				Cr: []uint8{
+					0xE0, 0xE0, 0x80, 0x80, 0x80, 0x80,
+					0xE0, 0xE0, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x40, 0x40, 0x80, 0x80,
+					0x80, 0x80, 0x40, 0x40, 0x80, 0x80,
+				},
+				YStride: 6,
+				CStride: 6,
+				Rect:    image.Rect(0, 0, 6, 6),
+			},
+		},
 		"I422": {
 			src: &image.YCbCr{
 				SubsampleRatio: image.YCbCrSubsampleRatio422,
@@ -155,6 +245,82 @@ func TestScale(t *testing.T) {
 				Rect:    image.Rect(0, 0, 4, 4),
 			},
 		},
+		"I422SameSize": {
+			src: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio422,
+				Y: []uint8{
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x20, 0x80, 0x80,
+					0x20, 0x20, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0xE0, 0xE0,
+					0x80, 0x80, 0xE0, 0xE0,
+				},
+				Cr: []uint8{
+					0xE0, 0xE0, 0x80, 0x80,
+					0xE0, 0xE0, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0xF0, 0xF0, 0x40, 0x40,
+					0xF0, 0xF0, 0x40, 0x40,
+				},
+				YStride: 8,
+				CStride: 4,
+				Rect:    image.Rect(0, 0, 8, 8),
+			},
+			width:  8,
+			height: 8,
+			expected: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio422,
+				Y: []uint8{
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x20, 0x80, 0x80,
+					0x20, 0x20, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0xE0, 0xE0,
+					0x80, 0x80, 0xE0, 0xE0,
+				},
+				Cr: []uint8{
+					0xE0, 0xE0, 0x80, 0x80,
+					0xE0, 0xE0, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0x80, 0x80, 0x80, 0x80,
+					0xF0, 0xF0, 0x40, 0x40,
+					0xF0, 0xF0, 0x40, 0x40,
+				},
+				YStride: 8,
+				CStride: 4,
+				Rect:    image.Rect(0, 0, 8, 8),
+			},
+		},
 		"I420": {
 			src: &image.YCbCr{
 				SubsampleRatio: image.YCbCrSubsampleRatio420,
@@ -207,6 +373,118 @@ func TestScale(t *testing.T) {
 				Rect:    image.Rect(0, 0, 4, 4),
 			},
 		},
+		"I420SameSize": {
+			src: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio420,
+				Y: []uint8{
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x20, 0x80, 0x80,
+					0x20, 0x20, 0x80, 0x80,
+					0x80, 0x80, 0xE0, 0xE0,
+					0x80, 0x80, 0xE0, 0xE0,
+				},
+				Cr: []uint8{
+					0xE0, 0xE0, 0x80, 0x80,
+					0xE0, 0xE0, 0x80, 0x80,
+					0xF0, 0xF0, 0x40, 0x40,
+					0xF0, 0xF0, 0x40, 0x40,
+				},
+				YStride: 8,
+				CStride: 4,
+				Rect:    image.Rect(0, 0, 8, 8),
+			},
+			width:  8,
+			height: 8,
+			expected: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio420,
+				Y: []uint8{
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x20, 0x80, 0x80,
+					0x20, 0x20, 0x80, 0x80,
+					0x80, 0x80, 0xE0, 0xE0,
+					0x80, 0x80, 0xE0, 0xE0,
+				},
+				Cr: []uint8{
+					0xE0, 0xE0, 0x80, 0x80,
+					0xE0, 0xE0, 0x80, 0x80,
+					0xF0, 0xF0, 0x40, 0x40,
+					0xF0, 0xF0, 0x40, 0x40,
+				},
+				YStride: 8,
+				CStride: 4,
+				Rect:    image.Rect(0, 0, 8, 8),
+			},
+		},
+		"I420NonSquareImage": {
+			src: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio420,
+				Y: []uint8{
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0xF0, 0xF0, 0x10, 0x10,
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0xF0, 0xF0, 0x10, 0x10,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00, 0x30, 0x30, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00, 0x30, 0x30, 0x00, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x20, 0x80, 0x80, 0x50, 0x50,
+					0x20, 0x20, 0x80, 0x80, 0x50, 0x50,
+					0x80, 0x80, 0xE0, 0xE0, 0x30, 0x30,
+					0x80, 0x80, 0xE0, 0xE0, 0x30, 0x30,
+				},
+				Cr: []uint8{
+					0xE0, 0xE0, 0x80, 0x80, 0xB0, 0xB0,
+					0xE0, 0xE0, 0x80, 0x80, 0xB0, 0xB0,
+					0xF0, 0xF0, 0x40, 0x40, 0xC0, 0xC0,
+					0xF0, 0xF0, 0x40, 0x40, 0xC0, 0xC0,
+				},
+				YStride: 12,
+				CStride: 6,
+				Rect:    image.Rect(0, 0, 12, 8),
+			},
+			width:  6,
+			height: 4,
+			expected: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio420,
+				Y: []uint8{
+					0xF0, 0x10, 0x00, 0x00, 0xF0, 0x10,
+					0x00, 0x00, 0x40, 0x00, 0x40, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x80, 0x30, 0x00, 0x30, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x80, 0x50,
+					0x80, 0xE0, 0x30,
+				},
+				Cr: []uint8{
+					0xE0, 0x80, 0xB0,
+					0xF0, 0x40, 0xC0,
+				},
+				YStride: 6,
+				CStride: 3,
+				Rect:    image.Rect(0, 0, 6, 4),
+			},
+		},
 	}
 	for name, algo := range scalerTestAlgos {
 		algo := algo
@@ -247,6 +525,100 @@ func TestScale(t *testing.T) {
 	}
 }

+func TestScaleFastBoxSampling(t *testing.T) {
+	cases := map[string]struct {
+		src           image.Image
+		width, height int
+		expected      image.Image
+	}{
+		"I420NonSquareImage": {
+			src: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio420,
+				Y: []uint8{
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0xF0, 0xF0, 0x10, 0x10,
+					0xF0, 0xF0, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0xF0, 0xF0, 0x10, 0x10,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00, 0x40, 0x40, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00, 0x30, 0x30, 0x00, 0x00,
+					0x00, 0x00, 0x80, 0x80, 0x30, 0x30, 0x00, 0x00, 0x30, 0x30, 0x00, 0x00,
+				},
+				Cb: []uint8{
+					0x20, 0x20, 0x80, 0x80, 0x50, 0x50,
+					0x20, 0x20, 0x80, 0x80, 0x50, 0x50,
+					0x80, 0x80, 0xE0, 0xE0, 0x30, 0x30,
+					0x80, 0x80, 0xE0, 0xE0, 0x30, 0x30,
+				},
+				Cr: []uint8{
+					0xE0, 0xE0, 0x80, 0x80, 0xB0, 0xB0,
+					0xE0, 0xE0, 0x80, 0x80, 0xB0, 0xB0,
+					0xF0, 0xF0, 0x40, 0x40, 0xC0, 0xC0,
+					0xF0, 0xF0, 0x40, 0x40, 0xC0, 0xC0,
+				},
+				YStride: 12,
+				CStride: 6,
+				Rect:    image.Rect(0, 0, 12, 8),
+			},
+			width:  6,
+			height: 4,
+			expected: &image.YCbCr{
+				SubsampleRatio: image.YCbCrSubsampleRatio420,
+				Y: []uint8{
+					0xF0, 0x80, 0x08, 0x00, 0x78, 0x80,
+					0x08, 0x00, 0x20, 0x20, 0x20, 0x20,
+					0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+					0x00, 0x40, 0x58, 0x18, 0x18, 0x18,
+				},
+				Cb: []uint8{
+					0x20, 0x50, 0x68,
+					0x68, 0xB0, 0x88,
+				},
+				Cr: []uint8{
+					0xE0, 0xB0, 0x98,
+					0xD0, 0x98, 0x80,
+				},
+				YStride: 6,
+				CStride: 3,
+				Rect:    image.Rect(0, 0, 6, 4),
+			},
+		},
+	}
+
+	for name, c := range cases {
+		c := c
+		t.Run(name, func(t *testing.T) {
+			trans := Scale(c.width, c.height, ScalerFastBoxSampling)
+			r := trans(ReaderFunc(func() (image.Image, func(), error) {
+				return c.src, func() {}, nil
+			}))
+			for i := 0; i < 4; i++ {
+				out, _, err := r.Read()
+				if err != nil {
+					t.Fatalf("Unexpected error: %v", err)
+				}
+				if !reflect.DeepEqual(c.expected, out) {
+					t.Errorf("Expected output image:\n%v\ngot:\n%v\nrepeat: %d", c.expected, out, i)
+				}
+				// Destroy output contents
+				switch v := out.(type) {
+				case *image.RGBA:
+					v.Stride = 10
+					v.Pix = v.Pix[:1]
+					v.Rect.Max.X = 1
+				case *image.YCbCr:
+					v.YStride = 10
+					v.CStride = 100
+					v.Y = v.Y[:1]
+					v.Cb = v.Cb[:2]
+					v.Cr = v.Cr[:1]
+					v.Rect.Max.X = 1
+				}
+			}
+		})
+	}
+}
+
 func BenchmarkScale(b *testing.B) {
 	for name, algo := range scalerBenchAlgos {
 		algo := algo
--- a/pkg/io/video/scaler_cgo.c
+++ b/pkg/io/video/scaler_cgo.c
@@ -29,7 +29,7 @@ void fastBoxSampling(
    const int sw, const int sh, const int sstride,
    uint32_t* tmp)
 {
-  memset(tmp, 0, dw * dh * ch);
+  memset(tmp, 0, dw * dh * ch * sizeof(tmp[0]));

  for (int sy = 0; sy < sh; sy++)
  {
--- a/pkg/io/video/scaleycrcb.go
+++ b/pkg/io/video/scaleycrcb.go
@@ -30,10 +30,18 @@ func (p *rgbLikeYCbCr) At(x, y int) color.Color {
 }

 func (p *rgbLikeYCbCr) Set(x, y int, c color.Color) {
-	rgb := c.(*color.RGBA64)
-	p.y.SetGray(x, y, color.Gray{uint8(rgb.R / 0x100)})
-	if (image.Point{x, y}.In(p.cb.Rect)) {
-		p.cb.SetGray(x, y, color.Gray{uint8(rgb.G / 0x100)})
-		p.cr.SetGray(x, y, color.Gray{uint8(rgb.B / 0x100)})
+	switch v := c.(type) {
+	case color.RGBA:
+		p.y.SetGray(x, y, color.Gray{v.R})
+		if (image.Point{x, y}.In(p.cb.Rect)) {
+			p.cb.SetGray(x, y, color.Gray{v.G})
+			p.cr.SetGray(x, y, color.Gray{v.B})
+		}
+	case *color.RGBA64:
+		p.y.SetGray(x, y, color.Gray{uint8(v.R / 0x100)})
+		if (image.Point{x, y}.In(p.cb.Rect)) {
+			p.cb.SetGray(x, y, color.Gray{uint8(v.G / 0x100)})
+			p.cr.SetGray(x, y, color.Gray{uint8(v.B / 0x100)})
+		}
 	}
 }
Author	SHA1	Message	Date
f-fl0	548cdac668	Fix scaling functions (#385 ) This commit corrects two small errors that causes the improper results reported in #312. - A copy paste typo (most likely) which sets the Dy component of the image rectangle to Dx. - The tmp array in fastBoxSampling was not properly reset because the last argument in memset should be the number of bytes to fill in and not the number of elements.	2022-03-18 15:04:36 +09:00
renovate[bot]	79f9fc31f6	Update golang.org/x/image commit hash to 723b81c (#370 ) Generated by Renovate Bot Co-authored-by: Renovate Bot <bot@renovateapp.com>	2022-03-17 16:09:36 +09:00
Renovate Bot	1f92ea40da	Update actions/setup-go action to v3 Generated by Renovate Bot	2022-03-14 10:34:25 -04:00
Renovate Bot	4beb7e5a23	Update actions/checkout action to v3 Generated by Renovate Bot	2022-03-14 10:34:10 -04:00
adamroach	9bb5755cd2	Fixing Stride Handling for OpenH264 (#381 ) The golang image.YCbCr struct can contain fields of arbitrary stride lengths, which don't necessarily match the field widths. This patch passes the stride values from the image.YCbCr struct into the OpenH264 encode calls.	2022-03-08 03:09:01 -06:00