Benchmark: Render to image (scaled) vs render to canvas

HTML Preparation code:

<canvas id='canvas' width='512' height='512'></canvas>
<img id="image" width='64' height='64' />

Script Preparation code:

var ctx = document.getElementById('canvas').getContext('2d');
var imageData = ctx.getImageData(0,0,512,512);

Tests:

Render image
var img = document.getElementById("image"); ctx.drawImage(img, 0, 0, 64, 64);
Render to canvas
ctx.putImageData(imageData,0,0);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Render image
Render to canvas

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36

Browser/OS: Chrome 129 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Render image	2482746.8 Ops/sec
Render to canvas	2368.4 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmarking setup and explain what's being tested.

**Benchmark Overview**

The test compares two approaches for rendering images:

1. **Rendering to image**: The goal is to render an image from a canvas element, specifically resizing it to 64x64 pixels.
2. **Rendering to canvas**: This involves drawing the original image directly onto a canvas element.

**Comparison Options**

There are two main comparison options:

* **Rendering to image (scaled)**: This approach uses `drawImage` method to resize the image on the fly, creating an intermediate image. The resized image is then discarded.
* **Rendering to canvas**: In this approach, the original image is drawn directly onto a canvas element using `putImageData`.

**Pros and Cons of each Approach**

1. **Rendering to Image (Scaled)**:
	* Pros:
		+ Avoids unnecessary memory allocations for the original image.
		+ Can be faster since it doesn't require drawing the entire image at once.
	* Cons:
		+ Requires extra computation to resize the image, which can add overhead.
		+ Discards the resized image after rendering, making the approach less efficient in terms of reusing the rendered image.
2. **Rendering to Canvas**:
	* Pros:
		+ Reuses the original image for subsequent renderings, reducing memory allocations and improving efficiency.
		+ Can be faster since it only requires drawing the entire image once.
	* Cons:
		+ May require more memory allocations if the same image is drawn multiple times.

**Library/Functionality Usage**

In this benchmark, the following libraries/functions are used:

* `document.getElementById` (DOM manipulation)
* `getContext('2d')` (2D canvas context creation)
* `getImageData` (canvas API for accessing pixel data)
* `drawImage` (drawing images on a canvas)
* `putImageData` (writing pixel data to a canvas)

**Special JS Features/Syntax**

This benchmark doesn't use any special JavaScript features or syntax beyond the standard DOM and canvas APIs.

**Other Alternatives**

If the benchmark were to be modified, alternative approaches could include:

1. **Using a graphics library**: A library like CanvasJS or Fabric.js could provide additional optimizations for rendering images.
2. **Optimizing image resizing algorithms**: Using optimized image resizing algorithms, such as those provided by libraries like Sharp.js, might improve performance.
3. **Using Web Workers**: Running the image rendering tasks in parallel using Web Workers could potentially speed up the benchmark.

However, these alternatives would require significant changes to the benchmark setup and script preparation code.

In summary, the current benchmark compares two common approaches for rendering images: resizing an image on the fly (rendering to image) versus drawing the original image directly onto a canvas element. The choice of approach depends on trade-offs between memory usage, computation overhead, and efficiency.

Related benchmarks:

Render to image (scaled) vs render to canvas (version: 1)

Comparing performance of: Render image vs Render to canvas

Created: 6 years ago by: Registered User

Jump to the latest result

Render image

Render to canvas

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):