feat: introduce vips image processor

For simplicity of implementation, ruby-vips gem is required even when not using the new processor

At the beginning, only colour profile conversion and size-related restrictions are implemented,
the other operations will be introduced iteratively

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## UNRELEASED
+### Added
+- Vips image processor
+
 ## [0.99.4] 18.11.2024
 ### Added
 - Better test coverage for straighten operation

Dockerfile

@@ -13,6 +13,7 @@ RUN apt-get update && apt-get install -yyq --no-install-recommends \
   libgirepository1.0-dev \
   # At the time of writing, "time" package is only required for benchmark
   time \
+  libvips \
   && apt-get clean \
   && rm -rf /va/lib/apt/lists/*
 

Gemfile.lock

@@ -8,6 +8,7 @@ PATH
       gdk_pixbuf2 (~> 4.0)
       pango (~> 4.0)
       rake-compiler (~> 1.2)
+      ruby-vips
 
 GEM
   remote: https://rubygems.org/
@@ -61,6 +62,7 @@ GEM
     listen (3.9.0)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
+    logger (1.6.1)
     lumberjack (1.2.10)
     matrix (0.4.2)
     method_source (1.1.0)
@@ -121,6 +123,9 @@ GEM
     rubocop-ast (1.32.3)
       parser (>= 3.3.1.0)
     ruby-progressbar (1.13.0)
+    ruby-vips (2.2.2)
+      ffi (~> 1.12)
+      logger
     shellany (0.0.1)
     simplecov (0.22.0)
       docile (~> 1.1)

lib/morandi.rb

@@ -7,6 +7,7 @@
 require 'morandi/pixbuf_ext'
 require 'morandi/errors'
 require 'morandi/image_processor'
+require 'morandi/vips_image_processor'
 require 'morandi/redeye'
 require 'morandi/crop_utils'
 
@@ -42,9 +43,20 @@ module Morandi
   # @param target_path [String] target location for image
   # @param local_options [Hash] Hash of options other than desired transformations
   # @option local_options [String] 'path.icc' A path to store the input after converting to sRGB colour space
+  # @options local_options [String] 'processor' ('pixbuf') Name of the image processing library ('pixbuf', 'vips')
   def process(source, options, target_path, local_options = {})
-    pro = ImageProcessor.new(source, options, local_options)
-    pro.result
-    pro.write_to_jpeg(target_path)
+    case local_options['processor']
+    when 'vips'
+      # Cache saves time in expense of RAM when performing the same processing multiple times
+      # Cache is also created for files based on their names, which can lead to leaking files data, so in terms
+      # of security it feels prudent to disable it. Latest libvips supports "revalidate" option to prevent that risk
+      cache_max = 0
+      concurrency = 2 # Hardcoding to 2 for now to maintain some balance between resource usage and performance
+      VipsImageProcessor.with_global_options(cache_max: cache_max, concurrency: concurrency) do
+        VipsImageProcessor.new(source, options).write_to_jpeg(target_path)
+      end
+    else
+      ImageProcessor.new(source, options, local_options).tap(&:result).write_to_jpeg(target_path)
+    end
   end
 end

lib/morandi/vips_image_processor.rb

@@ -0,0 +1,77 @@
+# frozen_string_literal: true
+
+require 'vips'
+
+require 'morandi/srgb_conversion'
+
+module Morandi
+  # An alternative to ImageProcessor which is based on libvips for faster and less resource-intensive processing
+  class VipsImageProcessor
+    # Vips options are global, this method sets them for yielding, then restores to original
+    def self.with_global_options(cache_max:, concurrency:)
+      previous_cache_max = Vips.cache_max
+      previous_concurrency = Vips.concurrency
+
+      Vips.cache_set_max(cache_max)
+      Vips.concurrency_set(concurrency)
+
+      yield
+    ensure
+      Vips.cache_set_max(previous_cache_max)
+      Vips.concurrency_set(previous_concurrency)
+    end
+
+    def initialize(path, user_options)
+      @path = path
+
+      @options = user_options
+
+      @size_limit_on_load_px = @options['output.max']
+      @output_width = @options['output.width']
+      @output_height = @options['output.height']
+    end
+
+    def process!
+      source_file_path = Morandi::SrgbConversion.perform(@path) || @path
+      begin
+        @img = Vips::Image.new_from_file(source_file_path)
+      rescue Vips::Error => e
+        # Match the known errors
+        raise UnknownTypeError if /is not a known file format/.match?(e.message)
+        raise CorruptImageError if /Premature end of JPEG file/.match?(e.message)
+
+        # Re-raise generic Error when unknown
+        raise Error, e.message
+      end
+      if @size_limit_on_load_px
+        @scale = @size_limit_on_load_px.to_f / [@img.width, @img.height].max
+        @img = @img.resize(@scale) if not_equal_to_one(@scale)
+      else
+        @scale = 1.0
+      end
+
+      return unless @options['output.limit'] && @output_width && @output_height
+
+      scale_factor = [@output_width, @output_height].max.to_f / [@img.width, @img.height].max
+      @img = @img.resize(scale_factor) if scale_factor < 1.0
+    end
+
+    def write_to_png(_write_to, _orientation = :any)
+      raise 'not implemented'
+    end
+
+    def write_to_jpeg(write_to, quality = nil)
+      process!
+
+      quality ||= @options.fetch('quality', 97)
+
+      @img.write_to_file(write_to, Q: quality)
+    end
+
+    private
+
+    def not_equal_to_one(float)
+      (float - 1.0).abs >= Float::EPSILON
+    end
+  end
+end

morandi.gemspec

@@ -29,4 +29,5 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'gdk_pixbuf2', '~> 4.0'
   spec.add_dependency 'pango', '~> 4.0'
   spec.add_dependency 'rake-compiler', '~> 1.2'
+  spec.add_dependency 'ruby-vips'
 end

spec/morandi_spec.rb

@@ -49,7 +49,7 @@
     let(:reference_image_prefix) { processor_name == 'pixbuf' ? '' : processor_name }
     subject(:process_image) { Morandi.process(file_arg, options, file_out, { 'processor' => processor_name }) }
 
-    describe 'when given an input without any options' do
+    describe 'when given an input without any options', vips_wip: processor_name == 'vips' do
       it 'creates output' do
         process_image
         expect(File).to exist(file_out)
@@ -87,7 +87,7 @@
       end
     end
 
-    describe 'with a big image and a bigger cropped area to fill' do
+    describe 'with a big image and a bigger cropped area to fill', vips_wip: processor_name == 'vips' do
       let(:options) do
         {
           'crop' => '0,477,15839,18804',
@@ -111,7 +111,7 @@
     describe 'when given an angle of rotation' do
       let(:options) { { 'angle' => angle } }
 
-      context '90 degress' do
+      context '90 degress', vips_wip: processor_name == 'vips' do
         let(:angle) { 90 }
 
         it 'rotates the image' do
@@ -120,7 +120,7 @@
         end
       end
 
-      context '180 degress' do
+      context '180 degress', vips_wip: processor_name == 'vips' do
         let(:angle) { 180 }
 
         it 'rotates the image' do
@@ -129,7 +129,7 @@
         end
       end
 
-      context '270 degress' do
+      context '270 degress', vips_wip: processor_name == 'vips' do
         let(:angle) { 270 }
 
         it 'rotates the image' do
@@ -138,7 +138,7 @@
         end
       end
 
-      context '360 degress' do
+      context '360 degress', vips_wip: processor_name == 'vips' do
         let(:angle) { 360 }
 
         it 'does not perform any rotation' do
@@ -148,7 +148,7 @@
       end
     end
 
-    context 'when give a "crop" option' do
+    context 'when give a "crop" option', vips_wip: processor_name == 'vips' do
       let(:cropped_width) { 300 }
       let(:cropped_height) { 300 }
 
@@ -223,7 +223,7 @@
       end
     end
 
-    describe 'when given an output.max option' do
+    describe 'when given an output.max option', vips_wip: processor_name == 'vips' do
       let(:options) { { 'output.max' => max_size } }
       let(:max_size) { 200 }
 
@@ -238,7 +238,7 @@
       end
     end
 
-    describe 'when given a straighten option' do
+    describe 'when given a straighten option', vips_wip: processor_name == 'vips' do
       let(:options) { { 'straighten' => 5 } }
 
       it 'straightens images' do
@@ -278,7 +278,7 @@
       end
     end
 
-    describe 'when given a gamma option' do
+    describe 'when given a gamma option', vips_wip: processor_name == 'vips' do
       let(:options) { { 'gamma' => 2.0 } }
 
       it 'should apply the gamma to the image' do
@@ -291,7 +291,7 @@
       end
     end
 
-    describe 'when given an fx option' do
+    describe 'when given an fx option', vips_wip: processor_name == 'vips' do
       let(:options) { { 'fx' => filter_name } }
 
       context 'with sepia' do
@@ -331,7 +331,7 @@
       end
     end
 
-    describe 'when changing the dimensions and auto-cropping' do
+    describe 'when changing the dimensions and auto-cropping', vips_wip: processor_name == 'vips' do
       let(:max_width) { 300 }
       let(:max_height) { 200 }
 
@@ -389,7 +389,7 @@
       end
     end
 
-    context 'with non-sRGB colour profile' do
+    context 'with non-sRGB colour profile', vips_wip: processor_name == 'vips' do
       let(:file_in) { 'spec/fixtures/pumpkins-icc-adobe-rgb-1998.jpg' }
 
       it 'converts the profile to sRGB' do
@@ -431,7 +431,7 @@
       end
     end
 
-    context 'with transparent png input' do
+    context 'with transparent png input', vips_wip: processor_name == 'vips' do
       let(:file_in) { 'spec/fixtures/match-with-transparency.png' }
       let(:options) do
         {
@@ -463,7 +463,7 @@
       end
     end
 
-    context 'with a non-rgb image' do
+    context 'with a non-rgb image', vips_wip: processor_name == 'vips' do
       let(:generate_image) do
         generate_test_image_greyscale(file_in, width: original_image_width, height: original_image_height)
       end
@@ -751,4 +751,8 @@
       end
     end
   end
+
+  context 'vips processor' do
+    it_behaves_like 'an image processor', 'vips'
+  end
 end

spec/spec_helper.rb

@@ -60,6 +60,10 @@
     puts "Visual report is available here: #{VisualReportHelper.visual_report_path}"
     puts 'Coverage report is here: coverage/index.html'
   end
+
+  config.before(:each, vips_wip: true) do
+    pending('Vips WIP')
+  end
 end
 
 RSpec::Matchers.define :be_redish do