add image support

Signed-off-by: Jade Abraham <jade.abraham@hpe.com>

Author: jabraham17

01-heat-1D-serial.chpl

@@ -1,3 +1,5 @@
+use ImageUtils;
+
 config const nx = 100000;
 config const N = 10000;
 const alpha = 0.1;
@@ -9,9 +11,12 @@ var u: [omega] real = 1.0;
 u[nx/4..3*nx/4] = 2.0;
 var un = u;
 
+writeImage(u);
+
 for 1..N {
   un <=> u;
   for i in omegaHat do
     u[i] = un[i] + alpha *
 	   (un[i-1] - 2*un[i] + un[i+1]);
+  writeImage(u);
 }

02-heat-1D-buggy.chpl

@@ -1,3 +1,5 @@
+use ImageUtils;
+
 config const nx = 100000;
 config const N = 10000;
 const alpha = 0.1;
@@ -9,9 +11,12 @@ var u: [omega] real = 1.0;
 u[nx/4..3*nx/4] = 2.0;
 var un = u;
 
+writeImage(u);
+
 for 1..N {
   un <=> u;
   for i in omega do
     u[i] = un[i] + alpha *
 	   (un[i-1] - 2*un[i] + un[i+1]);
+  writeImage(u);
 }

03-heat-1D.chpl

@@ -1,3 +1,5 @@
+use ImageUtils;
+
 config const nx = 100000;
 config const N = 10000;
 const alpha = 0.1;
@@ -9,9 +11,12 @@ var u: [omega] real = 1.0;
 u[nx/4..3*nx/4] = 2.0;
 var un = u;
 
+writeImage(u);
+
 for 1..N {
   un <=> u;
   forall i in omegaHat do
     u[i] = un[i] + alpha *
 	   (un[i-1] - 2*un[i] + un[i+1]);
+  writeImage(u);
 }

07-heat-1D-block.chpl

@@ -1,4 +1,5 @@
 use BlockDist;
+use ImageUtils;
 
 config const nx = 100000;
 config const N = 10000;
@@ -11,9 +12,12 @@ var u: [omega] real = 1.0;
 u[nx/4..3*nx/4] = 2.0;
 var un = u;
 
+writeImage(u);
+
 for 1..N {
   un <=> u;
   forall i in omegaHat do
     u[i] = un[i] + alpha *
 	   (un[i-1] - 2*un[i] + un[i+1]);
+  writeImage(u);
 }

08-heat-2D.chpl

@@ -1,3 +1,5 @@
+use ImageUtils;
+
 config const nx, ny = 1000;
 config const N = 10000;
 const alpha = 0.1;
@@ -9,11 +11,14 @@ var u: [omega] real = 1.0;
 u[nx/4..nx/2, ny/4..ny/2] = 2.0;
 var un = u;
 
+writeImage(u);
+
 for 1..N {
   un <=> u;
   forall (i, j) in omegaHat do
     u[i, j] = un[i, j] + alpha * (
 	       un[i-1, j] + un[i, j-1] +
 	       un[i+1, j] + un[i, j+1] -
 	       4 * un[i, j]);
+  writeImage(u);
 }

09-heat-2D-block.chpl

@@ -1,4 +1,5 @@
 use BlockDist;
+use ImageUtils;
 
 config const nx, ny = 1000;
 config const N = 10000;
@@ -11,11 +12,14 @@ var u: [omega] real = 1.0;
 u[nx/4..nx/2, ny/4..ny/2] = 2.0;
 var un = u;
 
+writeImage(u);
+
 for 1..N {
   un <=> u;
   forall (i, j) in omegaHat do
     u[i, j] = un[i, j] + alpha * (
 	       un[i-1, j] + un[i, j-1] +
 	       un[i+1, j] + un[i, j+1] -
 	       4 * un[i, j]);
+  writeImage(u);
 }

10-heat-2D-stencil.chpl

@@ -1,4 +1,5 @@
 use StencilDist;
+use ImageUtils;
 
 config const nx, ny = 1000;
 config const N = 10000;
@@ -11,11 +12,14 @@ var u: [omega] real = 1.0;
 u[nx/4..nx/2, ny/4..ny/2] = 2.0;
 var un = u;
 
+writeImage(u);
+
 for 1..N {
   un <=> u;
   forall (i, j) in omegaHat do
     u[i, j] = un[i, j] + alpha * (
 	       un[i-1, j] + un[i, j-1] +
 	       un[i+1, j] + un[i, j+1] -
 	       4 * un[i, j]);
+  writeImage(u);
 }

ImageUtils.chpl

@@ -0,0 +1,51 @@
+module ImageUtils {
+  public use Image;
+
+  /* Controls whether an image is printed */
+  config const image = false;
+  /* A factor to scale the image by */
+  config const imageScale = 1;
+  /* The framerate of the video */
+  config const framerate = 10;
+  /* The height of the image, only applicable for 1D input data */
+  config const imageHeight = 256;
+
+  private proc checkDimsHelper(width: int, height: int) {
+    if height < 64 then
+      halt("Image of minimum height 64 is required, got ", height);
+    if width > 4000 then
+      halt("Image of maximum width 4000 is required, got ", width);
+  }
+  private proc checkDims(data: [?d]) where d.isRectangular() && d.rank == 2 do
+    checkDimsHelper(data.dim(1).size, data.dim(0).size);
+  private proc checkDims(data: [?d]) where d.isRectangular() && d.rank == 1 do
+    checkDimsHelper(d.size, imageHeight);
+
+
+  private proc processFrameData(data: [?d]) where d.isRectangular() && d.rank == 1 {
+    // make the 1d data into 2d data of a specific height
+    var data2d: [0..#imageHeight, d.lowBound..d.highBound] data.eltType;
+    for i in 0..#imageHeight do
+      data2d[i,..] = data;
+
+    return processFrameData(data2d);
+  }
+  private proc processFrameData(data: [?d]) where d.isRectangular() && d.rank == 2 {
+    // create a white border around the image and turn raw data into pixels
+    var image: [data.domain.expand(1)] int = 0xFFFFFF;
+    image[data.domain] = interpolateColor(data, 0x000000, 0x0000FF);
+
+    return scale(image, imageScale);
+  }
+
+  proc writeImage(u: []) throws {
+    if !image then return;
+
+    checkDims(u);
+
+    @functionStatic
+    ref pipe = try! new mediaPipe("heat.mp4", imageType.bmp, framerate);
+
+    pipe.writeFrame(processFrameData(u));
+  }
+}