feat(tiler-sharp): allow outputs to customise how output is compressed (#3126)

#### Motivation

TerrainRGB needs to be lossless compressed, this adds the abilities for
pipelines to customise how they create the output eg resizeKernels and
lossless parameters

#### Modification

allows outputs to define resize kernels

#### Checklist

_If not applicable, provide explanation of why._

- [ ] Tests updated
- [ ] Docs updated
- [ ] Issue linked in Title

Author: blacha

packages/config-loader/src/json/tiff.config.ts

@@ -428,7 +428,7 @@ export async function initConfigFromUrls(
   targets: URL[],
   concurrency = 25,
   log?: LogType,
-): Promise<{ tileSet: ConfigTileSetRaster; imagery: ConfigImageryTiff[] }> {
+): Promise<{ tileSet: ConfigTileSetRaster; tileSets: ConfigTileSetRaster[]; imagery: ConfigImageryTiff[] }> {
   const q = pLimit(concurrency);
 
   const imageryConfig: Promise<ConfigImageryTiff>[] = [];
@@ -451,23 +451,29 @@ export async function initConfigFromUrls(
     type: TileSetType.Raster,
     layers: [],
     outputs: [
+      {
+        title: 'TerrainRGB',
+        name: 'terrain-rgb',
+        pipeline: [{ type: 'terrain-rgb' }],
+        output: {
+          type: 'webp',
+          lossless: true,
+          background: { r: 1, g: 134, b: 160, alpha: 1 },
+          resizeKernel: { in: 'nearest', out: 'nearest' },
+        },
+      },
       {
         title: 'Color ramp',
         name: 'color-ramp',
         pipeline: [{ type: 'color-ramp' }],
         output: { type: 'webp' },
       },
-      {
-        title: 'TerrainRGB',
-        name: 'terrain-rgb',
-        pipeline: [{ type: 'terrain-rgb' }],
-        output: { type: 'webp', lossless: true },
-      },
     ],
   };
 
   provider.put(aerialTileSet);
   const configs = await Promise.all(imageryConfig);
+  const tileSets = [aerialTileSet];
   for (const cfg of configs) {
     if (isRgbOrRgba(cfg)) {
       let existingLayer = aerialTileSet.layers.find((l) => l.title === cfg.title);
@@ -484,10 +490,11 @@ export async function initConfigFromUrls(
       }
       existingLayer[cfg.projection] = cfg.id;
       provider.put(elevationTileSet);
+      tileSets.push(elevationTileSet);
     }
   }
   // FIXME: this should return all the tile sets that were created
-  return { tileSet: aerialTileSet, imagery: configs };
+  return { tileSet: aerialTileSet, tileSets, imagery: configs };
 }
 
 /**

packages/config/src/config/tile.set.ts

@@ -107,6 +107,13 @@ export interface ConfigTileSetRasterOutput {
      * {@link ConfigTileSetRaster.background} if not defined
      */
     background?: { r: number; g: number; b: number; alpha: number };
+
+    /**
+     * When scaling tiles in the rendering process what kernel to use
+     *
+     * will fall back to  {@link ConfigTileSetRaster.background} if not defined
+     */
+    resizeKernel?: { in: TileResizeKernel; out: TileResizeKernel };
   };
 }
 

packages/lambda-tiler/src/routes/preview.ts

@@ -147,12 +147,14 @@ export async function renderPreview(req: LambdaHttpRequest, ctx: PreviewRenderCo
     compositions.push(...result);
   }
 
+  const tileOutput = ctx.output;
   const tileContext = {
     layers: compositions,
-    format: ctx.output.output.type,
-    lossless: ctx.output.output.lossless,
-    background: ctx.output.output.background ?? ctx.tileSet.background ?? DefaultBackground,
-    resizeKernel: DefaultResizeKernel,
+    pipeline: tileOutput.pipeline,
+    format: tileOutput.output.type,
+    lossless: tileOutput.output.lossless,
+    background: tileOutput.output.background ?? ctx.tileSet.background ?? DefaultBackground,
+    resizeKernel: tileOutput.output.resizeKernel ?? ctx.tileSet.resizeKernel ?? DefaultResizeKernel,
   };
 
   // Load all the tiff tiles and resize/them into the correct locations

packages/lambda-tiler/src/routes/tile.xyz.raster.ts

@@ -139,7 +139,7 @@ export const TileXyzRaster = {
       format: tileOutput.output.type,
       lossless: tileOutput.output.lossless,
       background: tileOutput.output.background ?? tileSet.background ?? DefaultBackground,
-      resizeKernel: tileSet.resizeKernel ?? DefaultResizeKernel,
+      resizeKernel: tileOutput.output.resizeKernel ?? tileSet.resizeKernel ?? DefaultResizeKernel,
       metrics: req.timer,
     });
 

packages/server/src/config.ts

@@ -28,7 +28,13 @@ export async function loadConfig(opts: ServerOptions, logger: LogType): Promise<
   if ('paths' in opts) {
     const mem = new ConfigProviderMemory();
     const ret = await initConfigFromUrls(mem, opts.paths);
-    logger.info({ tileSet: ret.tileSet.name, layers: ret.tileSet.layers.length }, 'TileSet:Loaded');
+    for (const ts of ret.tileSets) {
+      logger.info(
+        { tileSet: ts.name, layers: ts.layers.length, outputs: ts.outputs?.map((f) => f.name) },
+        'TileSet:Loaded',
+      );
+    }
+
     for (const im of ret.imagery) {
       logger.info(
         { imagery: im.uri, title: im.title, tileMatrix: im.tileMatrix, files: im.files.length },

packages/tiler-sharp/src/index.ts

@@ -66,21 +66,29 @@ export class TileMakerSharp implements TileMaker {
   toImage(format: ImageFormat, pipeline: Sharp.Sharp, lossless?: boolean): Promise<Buffer> {
     switch (format) {
       case 'jpeg':
+        if (lossless) throw new Error('lossless jpeg is not defined');
         return pipeline.jpeg().toBuffer();
       case 'png':
         return pipeline.png().toBuffer();
       case 'webp':
-        return pipeline.webp({ lossless }).toBuffer();
+        if (lossless) return pipeline.webp({ lossless: true, quality: 100, alphaQuality: 100 }).toBuffer();
+        return pipeline.webp().toBuffer();
       case 'avif':
+        if (lossless) throw new Error('lossless avif is not defined');
         return pipeline.avif().toBuffer();
       default:
         throw new Error(`Invalid image format "${format}"`);
     }
   }
 
-  private async getImageBuffer(layers: SharpOverlay[], format: ImageFormat, background: Sharp.RGBA): Promise<Buffer> {
+  private async getImageBuffer(
+    layers: SharpOverlay[],
+    format: ImageFormat,
+    background: Sharp.RGBA,
+    lossless?: boolean,
+  ): Promise<Buffer> {
     if (layers.length === 0) return this.getEmptyImage(format, background);
-    return this.toImage(format, this.createImage(background).composite(layers));
+    return this.toImage(format, this.createImage(background).composite(layers), lossless);
   }
 
   public async compose(ctx: TileMakerContext): Promise<{ buffer: Buffer; metrics: Metrics; layers: number }> {
@@ -104,7 +112,7 @@ export class TileMakerSharp implements TileMaker {
     metrics.end('compose:overlay');
 
     metrics.start('compose:compress');
-    const buffer = await this.getImageBuffer(overlays, ctx.format, ctx.background);
+    const buffer = await this.getImageBuffer(overlays, ctx.format, ctx.background, ctx.lossless);
     metrics.end('compose:compress');
 
     return { buffer, metrics, layers: overlays.length };