Benchmark: PutImageData vs DrawImage

HTML Preparation code:

<canvas id='master' width='100' height='100'></canvas>
<canvas id='pid' width='100' height='100'></canvas>
<canvas id='di' width='100' height='100'></canvas>

Script Preparation code:

var master = document.getElementById('master');
var masterctx = master.getContext('2d');
var pid = document.getElementById('pid').getContext('2d');
var di = document.getElementById('di').getContext('2d');

masterctx.fillRect(0,0,50,50);
masterctx.fillStyle = "red";
masterctx.fillRect(50,50,100,100);

Tests:

DrawImage whole master into di canvas
di.drawImage(master,0,0);
PutImageData whole master into pid canvas
let imgData = masterctx.getImageData(0,0,100,100); pid.putImageData(imgData,0,0);
DrawImage half master into di canvas
di.drawImage(master,25,0,50,100,25,0,50,100);
PutImageData half master into pid canvas
let imgData = masterctx.getImageData(25,0,75,100); pid.putImageData(imgData,25,0);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
DrawImage whole master into di canvas
PutImageData whole master into pid canvas
DrawImage half master into di canvas
PutImageData half master into pid canvas

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what is being tested.

**Benchmark Overview**

The benchmark measures the performance of two approaches to retrieve and draw image data from one canvas onto another: `DrawImage` and `PutImageData`. The benchmark consists of four test cases:

1. Drawing the entire master image onto a destination image (`di.drawImage(master,0,0)`).
2. Retrieving the pixel data of the master image using `getImageData`, then drawing it onto the destination image using `putImageData` (`pid.putImageData(imgData,0,0)`).
3. Drawing only half of the master image onto the destination image (`di.drawImage(master,25,0,50,100,25,0,50,100)`).
4. Retrieving the pixel data of half of the master image using `getImageData`, then drawing it onto the destination image using `putImageData` (`pid.putImageData(imgData,25,0)`).

**Options Compared**

The two main options being compared are:

1. **DrawImage**: This approach directly draws the image from one canvas to another without retrieving the pixel data.
2. **PutImageData**: This approach retrieves the pixel data of an image using `getImageData`, then uses `putImageData` to draw it onto a new canvas.

**Pros and Cons**

Here are some pros and cons of each approach:

**DrawImage**

Pros:

* Fast, as it doesn't require retrieving pixel data.
* Can be optimized for performance by caching the image data.

Cons:

* May not work well with large images or complex compositions.
* Requires the destination canvas to have a matching size and aspect ratio.

**PutImageData**

Pros:

* Works with any size and aspect ratio of the source and destination canvases.
* Can handle complex compositions, such as transparency and clipping paths.

Cons:

* Slower than `DrawImage`, due to the overhead of retrieving pixel data.
* Requires more memory for storing the image data.

**Other Considerations**

The benchmark also considers the following factors:

* **Canvas caching**: Some browsers may cache canvas elements or their contents, which can affect performance. However, this is not explicitly tested in this benchmark.
* **Image compression**: The benchmark assumes that the images are stored as uncompressed binary data (i.e., no lossy compression). In a real-world scenario, images may be compressed, which could impact performance.

**Library and Syntax**

In this benchmark, the following libraries and syntax are used:

* `getCanvas()` and `getContext('2d')`: These functions are part of the HTML5 canvas API, which provides a 2D drawing context for rendering graphics.
* `drawImage()`, `putImageData()`, `getImageData()`: These methods are also part of the HTML5 canvas API.

**Special JS Features**

There are no special JavaScript features or syntax being used in this benchmark that are not commonly supported by modern browsers. However, it's worth noting that some older browsers may have issues with certain canvas APIs or properties.

Latest run results:

Run details: (Test run date: 19 hours ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 131 on Android

View result in a separate tab

Test name	Executions per second
DrawImage whole master into di canvas	219145.5 Ops/sec
PutImageData whole master into pid canvas	3287.3 Ops/sec
DrawImage half master into di canvas	2272.3 Ops/sec
PutImageData half master into pid canvas	3069.3 Ops/sec

Related benchmarks:

PutImageData vs DrawImage (version: 0)

GetImageData with PutImageData vs just DrawImage

Comparing performance of: DrawImage whole master into di canvas vs PutImageData whole master into pid canvas vs DrawImage half master into di canvas vs PutImageData half master into pid canvas

Created: 4 years ago by: Guest

Jump to the latest result

DrawImage whole master into di canvas

PutImageData whole master into pid canvas

DrawImage half master into di canvas

PutImageData half master into pid canvas

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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