Resizing, pillow style

Note: Downsample has been removed as that's the same as EResizeAlgo.BOX

Author: ollydev

DocGen/images/resample_roundtrip.png

@@ -0,0 +1,89 @@
+begin
+  asm
+    push   rsi
+    push   rdi
+    push   rbx
+    push   r12
+    push   r13
+    push   r14
+    push   r15
+    pxor   xmm3, xmm3                    // zero (byte->word unpack)
+    mov    eax, $2000                    // 1<<13 bias
+    movd   xmm4, eax
+    pshufd xmm4, xmm4, 0
+    mov    eax, $FF000000                // alpha-force mask
+    movd   xmm5, eax
+
+    mov    r8d, RowCount
+    test   r8d, r8d
+    jle    @@hdone
+    mov    r12, Src
+    mov    r13, Dst
+    mov    r14d, SrcStride
+    mov    r15d, OutDim
+  @@hrow:
+    mov    r10, Starts                   // reset per row (per-column tables)
+    mov    rbx, Counts
+    mov    r11, KK
+    xor    r9d, r9d                       // xx = 0
+  @@hxx:
+    cmp    r9d, r15d
+    jge    @@hrowend
+    mov    eax, dword ptr [r10]          // xmin
+    mov    ecx, dword ptr [rbx]          // count
+    lea    rsi, [r12 + rax*4]            // P = srcrow + xmin
+    mov    rdi, r11                       // K
+    pxor   xmm0, xmm0
+  @@hpair:
+    cmp    ecx, 2
+    jl     @@htail
+    movd   xmm1, dword ptr [rsi]
+    movd   xmm2, dword ptr [rsi+4]
+    punpcklbw xmm1, xmm2
+    punpcklbw xmm1, xmm3
+    movd   xmm2, dword ptr [rdi]
+    pshufd xmm2, xmm2, 0
+    pmaddwd xmm1, xmm2
+    paddd  xmm0, xmm1
+    add    rsi, 8
+    add    rdi, 4
+    sub    ecx, 2
+    jmp    @@hpair
+  @@htail:
+    test   ecx, ecx
+    jz     @@hstore
+    movd   xmm1, dword ptr [rsi]
+    punpcklbw xmm1, xmm1
+    punpcklbw xmm1, xmm3
+    movd   xmm2, dword ptr [rdi]
+    pshufd xmm2, xmm2, 0
+    pmaddwd xmm1, xmm2
+    paddd  xmm0, xmm1
+  @@hstore:
+    paddd  xmm0, xmm4
+    psrad  xmm0, 14
+    packssdw xmm0, xmm0
+    packuswb xmm0, xmm0
+    por    xmm0, xmm5
+    movd   dword ptr [r13 + r9*4], xmm0
+    add    r10, 4                         // Starts++
+    add    rbx, 4                         // Counts++
+    mov    edx, KSize
+    lea    r11, [r11 + rdx*2]
+    inc    r9d
+    jmp    @@hxx
+  @@hrowend:
+    lea    r12, [r12 + r14*4]            // srcrow += SrcStride
+    lea    r13, [r13 + r15*4]            // dstrow += OutDim
+    dec    r8d
+    jnz    @@hrow
+  @@hdone:
+    pop    r15
+    pop    r14
+    pop    r13
+    pop    r12
+    pop    rbx
+    pop    rdi
+    pop    rsi
+  end;
+end;

DocGen/images/resample_upscale.png

@@ -0,0 +1,89 @@
+begin
+  asm
+    push   rsi
+    push   rdi
+    push   r12
+    push   r13
+    push   r14
+    push   r15
+    pxor   xmm3, xmm3
+    mov    eax, $2000
+    movd   xmm4, eax
+    pshufd xmm4, xmm4, 0
+    mov    eax, $FF000000
+    movd   xmm5, eax
+
+    mov    r8d, RowCount
+    test   r8d, r8d
+    jle    @@vdone
+    mov    r13, Dst
+    mov    r15d, OutDim                   // row stride == width (src and dst)
+    mov    r10, Starts
+    mov    r14, Counts
+    mov    r11, KK
+  @@vrow:
+    mov    eax, dword ptr [r10]          // ymin
+    mov    ecx, dword ptr [r14]          // count
+    imul   rax, r15                       // ymin * stride
+    mov    r12, Src
+    lea    r12, [r12 + rax*4]            // srcbase = Src + ymin*stride
+    xor    r9d, r9d
+  @@vxx:
+    cmp    r9d, r15d
+    jge    @@vrowend
+    lea    rsi, [r12 + r9*4]             // P = srcbase + xx
+    mov    rdi, r11
+    mov    edx, ecx
+    pxor   xmm0, xmm0
+  @@vpair:
+    cmp    edx, 2
+    jl     @@vtail
+    movd   xmm1, dword ptr [rsi]
+    lea    rax, [rsi + r15*4]            // + one row
+    movd   xmm2, dword ptr [rax]
+    punpcklbw xmm1, xmm2
+    punpcklbw xmm1, xmm3
+    movd   xmm2, dword ptr [rdi]
+    pshufd xmm2, xmm2, 0
+    pmaddwd xmm1, xmm2
+    paddd  xmm0, xmm1
+    lea    rsi, [rsi + r15*8]            // += two rows
+    add    rdi, 4
+    sub    edx, 2
+    jmp    @@vpair
+  @@vtail:
+    test   edx, edx
+    jz     @@vstore
+    movd   xmm1, dword ptr [rsi]
+    punpcklbw xmm1, xmm1
+    punpcklbw xmm1, xmm3
+    movd   xmm2, dword ptr [rdi]
+    pshufd xmm2, xmm2, 0
+    pmaddwd xmm1, xmm2
+    paddd  xmm0, xmm1
+  @@vstore:
+    paddd  xmm0, xmm4
+    psrad  xmm0, 14
+    packssdw xmm0, xmm0
+    packuswb xmm0, xmm0
+    por    xmm0, xmm5
+    movd   dword ptr [r13 + r9*4], xmm0
+    inc    r9d
+    jmp    @@vxx
+  @@vrowend:
+    mov    edx, KSize
+    lea    r11, [r11 + rdx*2]
+    lea    r13, [r13 + r15*4]
+    add    r10, 4
+    add    r14, 4
+    dec    r8d
+    jnz    @@vrow
+  @@vdone:
+    pop    r15
+    pop    r14
+    pop    r13
+    pop    r12
+    pop    rdi
+    pop    rsi
+  end;
+end;

Source/asm/resamplehorizontal_x86_64.inc

@@ -36,6 +36,29 @@ implementation
 ```
 *)
 
+(*
+EImageResizeAlgo
+----------------
+```
+enum(NEAREST_NEIGHBOUR, BILINEAR, LANCZOS, BOX, HAMMING, BICUBIC)
+```
+The resampling filter used by `TImage.Resize`, from fastest to highest quality:
+
+- `NEAREST_NEIGHBOUR`: No blending - fastest, but blocky. Good for pixel-art.
+- `BOX`: Simple averaging - cheap, mainly for downscaling.
+- `BILINEAR`: Fast and smooth, but a little soft.
+- `HAMMING`: A little sharper than bilinear.
+- `BICUBIC`: Smooth and sharp - a good default.
+- `LANCZOS`: Sharpest and highest quality, but the slowest.
+
+![enlarging comparison](../../images/resample_upscale.png)
+![downscale and rebuild comparison](../../images/resample_roundtrip.png)
+
+```{note}
+This enum is scoped so use like `EImageResizeAlgo.BILINEAR`
+```
+*)
+
 (*
 TImage.Construct
 ----------------
@@ -654,8 +677,9 @@ procedure _LapeImage_ReplaceColorBinary2(const Params: PParamArray); LAPE_WRAPPE
 TImage.Resize
 -------------
 ```
-function TImage.Resize(Algo: EImageResizeAlgo; NewWidth, NewHeight: Integer): TSimbaImage;
+function TImage.Resize(Algo: EImageResizeAlgo; NewWidth, NewHeight: Integer): TImage;
 ```
+Returns a new image resized to `NewWidth` by `NewHeight`, sampled with the given `Algo` filter (see `EImageResizeAlgo`). The original image is left unchanged.
 *)
 procedure _LapeImage_Resize1(const Params: PParamArray; const Result: Pointer); LAPE_WRAPPER_CALLING_CONV
 begin
@@ -666,50 +690,38 @@ procedure _LapeImage_Resize1(const Params: PParamArray; const Result: Pointer);
 TImage.Resize
 -------------
 ```
-function TImage.Resize(Algo: EImageResizeAlgo; Scale: Single): TSimbaImage;
+function TImage.Resize(Algo: EImageResizeAlgo; Scale: Single): TImage;
 ```
+Resizes by a `Scale` factor instead of absolute dimensions - e.g. `0.5` halves the width and height and `2.0` doubles them.
 *)
 procedure _LapeImage_Resize2(const Params: PParamArray; const Result: Pointer); LAPE_WRAPPER_CALLING_CONV
 begin
   PLapeObjectImage(Result)^^ := PLapeObjectImage(Params^[0])^^.Resize(EImageResizeAlgo(Params^[1]^), PSingle(Params^[2])^);
 end;
 
 (*
-TImage.Rotate
+TImage.Resize
 -------------
 ```
-function TImage.Rotate(Algo: EImageRotateAlgo; Radians: Single; Expand: Boolean): TSimbaImage;
-```
-*)
-procedure _LapeImage_Rotate(const Params: PParamArray; const Result: Pointer); LAPE_WRAPPER_CALLING_CONV
-begin
-  PLapeObjectImage(Result)^^ := PLapeObjectImage(Params^[0])^^.Rotate(EImageRotateAlgo(Params^[1]^), PSingle(Params^[2])^, PBoolean(Params^[3])^);
-end;
-
-(*
-TImage.Downsample
------------------
-```
-function TImage.Downsample(Scale: Integer): TImage;
+function TImage.Resize(Algo: EImageResizeAlgo; NewWidth, NewHeight: Integer; IgnorePoints: TPointArray): TImage;
 ```
+Resize, but source pixels listed in `IgnorePoints` are excluded from sampling.
 *)
-procedure _LapeImage_DownSample1(const Params: PParamArray; const Result: Pointer); LAPE_WRAPPER_CALLING_CONV
+procedure _LapeImage_Resize3(const Params: PParamArray; const Result: Pointer); LAPE_WRAPPER_CALLING_CONV
 begin
-  PLapeObjectImage(Result)^^ := PLapeObjectImage(Params^[0])^^.Downsample(PInteger(Params^[1])^);
+  PLapeObjectImage(Result)^^ := PLapeObjectImage(Params^[0])^^.Resize(EImageResizeAlgo(Params^[1]^), PInteger(Params^[2])^, PInteger(Params^[3])^, PPointArray(Params^[4])^);
 end;
 
 (*
-TImage.Downsample
------------------
+TImage.Rotate
+-------------
 ```
-function TImage.Downsample(Scale: Integer; IgnorePoints: TPointArray): TImage;
+function TImage.Rotate(Algo: EImageRotateAlgo; Radians: Single; Expand: Boolean): TSimbaImage;
 ```
-
-Downsample but points in `IgnorePoints` are not sampled from.
 *)
-procedure _LapeImage_DownSample2(const Params: PParamArray; const Result: Pointer); LAPE_WRAPPER_CALLING_CONV
+procedure _LapeImage_Rotate(const Params: PParamArray; const Result: Pointer); LAPE_WRAPPER_CALLING_CONV
 begin
-  PLapeObjectImage(Result)^^ := PLapeObjectImage(Params^[0])^^.Downsample(PInteger(Params^[1])^, PPointArray(Params^[2])^);
+  PLapeObjectImage(Result)^^ := PLapeObjectImage(Params^[0])^^.Rotate(EImageRotateAlgo(Params^[1]^), PSingle(Params^[2])^, PBoolean(Params^[3])^);
 end;
 
 (*
@@ -1339,20 +1351,18 @@ procedure _LapeImage_Blend2(const Params: PParamArray; const Result: Pointer); L
 TImage.Blur
 -----------
 ```
-function TImage.Blur(Algo: EImageBlurAlgo; Radius: Integer): TSimbaImage;
-```
-
-Algo can be either EImageBlurAlgo.BOX, EImageBlurAlgo.GAUSS.
+function TImage.Blur(Algo: EImageBlurAlgo; Radius: Single): TSimbaImage;
+``
+Algo can be either `EImageBlurAlgo.BOX` or `EImageBlurAlgo.GAUSS`.
 
 ```{note}
-EImageBlurAlgo.GAUSS is not true gaussian blur it's an approximation (in linear time).
-
+Gauss is not true gaussian blur it's an approximation (in linear time).
 <https://blog.ivank.net/fastest-gaussian-blur.html>
 ```
 *)
 procedure _LapeImage_Blur(const Params: PParamArray; const Result: Pointer); LAPE_WRAPPER_CALLING_CONV
 begin
-  PLapeObjectImage(Result)^^ := PLapeObjectImage(Params^[0])^^.Blur(EImageBlurAlgo(Params^[1]^), PInteger(Params^[2])^);
+  PLapeObjectImage(Result)^^ := PLapeObjectImage(Params^[0])^^.Blur(EImageBlurAlgo(Params^[1]^), PSingle(Params^[2])^);
 end;
 
 (*
@@ -1685,7 +1695,7 @@ procedure ImportSimbaImage(Script: TSimbaScript);
 
     addGlobalType('array of TImage', 'TImageArray');
     addGlobalType('enum(WIDTH, HEIGHT, LINE)', 'EImageMirrorStyle');
-    addGlobalType('enum(NEAREST_NEIGHBOUR, BILINEAR)', 'EImageResizeAlgo');
+    addGlobalType('enum(NEAREST_NEIGHBOUR, BILINEAR, LANCZOS, BOX, HAMMING, BICUBIC)', 'EImageResizeAlgo');
     addGlobalType('enum(NEAREST_NEIGHBOUR, BILINEAR)', 'EImageRotateAlgo');
     addGlobalType('enum(BOX, GAUSS)', 'EImageBlurAlgo');
     addGlobalType('set of enum(LEFT, CENTER, RIGHT, JUSTIFY, TOP, VERTICAL_CENTER, BASE_LINE, BOTTOM)', 'EImageTextAlign');
@@ -1748,9 +1758,8 @@ procedure ImportSimbaImage(Script: TSimbaScript);
 
     addGlobalFunc('function TImage.Resize(Algo: EImageResizeAlgo; NewWidth, NewHeight: Integer): TImage; overload;', @_LapeImage_Resize1);
     addGlobalFunc('function TImage.Resize(Algo: EImageResizeAlgo; Scale: Single): TImage; overload;', @_LapeImage_Resize2);
+    addGlobalFunc('function TImage.Resize(Algo: EImageResizeAlgo; NewWidth, NewHeight: Integer; IgnorePoints: TPointArray): TImage; overload;', @_LapeImage_Resize3);
     addGlobalFunc('function TImage.Rotate(Algo: EImageRotateAlgo; Radians: Single; Expand: Boolean): TImage;', @_LapeImage_Rotate);
-    addGlobalFunc('function TImage.Downsample(Scale: Integer): TImage; overload', @_LapeImage_Downsample1);
-    addGlobalFunc('function TImage.Downsample(Scale: Integer; IgnorePoints: TPointArray): TImage; overload', @_LapeImage_Downsample2);
     addGlobalFunc('function TImage.Mirror(Style: EImageMirrorStyle): TImage', @_LapeImage_Mirror);
 
     addGlobalFunc('function TImage.TextWidth(Text: String): Integer;', @_LapeImage_TextWidth);
@@ -1815,7 +1824,7 @@ procedure ImportSimbaImage(Script: TSimbaScript);
     addGlobalFunc('function TImage.ThresholdAdaptiveSauvola(Invert: Boolean = False; Radius: Integer = 25; C: Single = 0.2): TImage', @_LapeImage_ThresholdAdaptiveSauvola);
     addGlobalFunc('function TImage.Blend(Points: TPointArray; Radius: Integer): TImage; overload', @_LapeImage_Blend1);
     addGlobalFunc('function TImage.Blend(Points: TPointArray; Radius: Integer; IgnorePoints: TPointArray): TImage; overload', @_LapeImage_Blend2);
-    addGlobalFunc('function TImage.Blur(Algo: EImageBlurAlgo; Radius: Integer): TImage;', @_LapeImage_Blur);
+    addGlobalFunc('function TImage.Blur(Algo: EImageBlurAlgo; Radius: Single): TImage;', @_LapeImage_Blur);
 
     addGlobalFunc('function TImage.ToGreyMatrix: TByteMatrix', @_LapeImage_ToGreyMatrix);
     addGlobalFunc('function TImage.ToMatrix: TIntegerMatrix; overload', @_LapeImage_ToMatrix1);