# Take screenshots of webpages or HTML files

Robot: `/html/convert`

🤖/html/convert takes screenshots of web pages or uploaded HTML pages.

A URL can be provided instead of an input HTML file, to capture a screenshot from the website referenced by the URL.

Use [🤖/image/resize](/docs/robots/image-resize.md) to resize or crop the screenshot as needed.

Stage: ga

## Usage example

Take a full screenshot of the Transloadit homepage:

```json
{
  "steps": {
    "captured": {
      "robot": "/html/convert",
      "url": "https://transloadit.com"
    }
  }
}
```

## Parameters

* `interpolate`: Controls whether Assembly Variables are interpolated for individual instruction fields.

  By default, most Robot instruction fields interpolate Assembly Variables. Set this to `false` to treat every instruction field as literal text, or set an individual field path to `false` to treat only that field as literal text. For Robot-specific fields that are literal by default, set this to `true` or set that field path to `true` to opt back into interpolation.

  Use field names such as `path`, or dotted paths such as `ffmpeg.vf` for nested objects.

* `output_meta`: Allows you to specify a set of metadata that is more expensive on CPU power to calculate, and thus is disabled by default to keep your Assemblies processing fast.

  For images, you can add `"has_transparency": true` in this object to extract if the image contains transparent parts and `"dominant_colors": true` to extract an array of hexadecimal color codes from the image.

  For images, you can also add `"blurhash": true` to extract a [BlurHash](https://blurha.sh) string — a compact representation of a placeholder for the image, useful for showing a blurred preview while the full image loads.

  For videos, you can add the `"colorspace": true` parameter to extract the colorspace of the output video.

  For videos, you can also add `"interlaced": true` to detect whether the video is interlaced. This combines the cheap ffprobe `field_order` flag with a bounded `idet` sampling pass over the first frames of the source, exposing `interlaced`, `field_order`, and a diagnostic `interlace_detection` object under `file.meta`. This is computationally expensive and billed accordingly.

  For audio, you can add `"mean_volume": true` to get a single value representing the mean average volume of the audio file.

  You can also set this to `false` to skip metadata extraction and speed up transcoding.

* `user_meta`: Adds custom metadata to each file emitted by this Robot without modifying the file’s contents.

  The values are merged with any existing `user_meta` carried by the input file. If both objects contain the same key, this Robot’s value takes precedence. Assembly Variables are supported, for example `{ "internal_file_id": "${file.id}" }`.

* `result`: Whether the results of this Step should be present in the Assembly Status JSON

* `queue`: Setting the queue to 'batch', manually downgrades the priority of jobs for this step to avoid consuming Priority job slots for jobs that don't need zero queue waiting times

* `force_accept`: Force a Robot to accept a file type it would have ignored.

  By default, Robots ignore files they are not familiar with.
  [🤖/video/encode](/docs/robots/video-encode.md), for
  example, will happily ignore input images.

  With the `force_accept` parameter set to `true`, you can force Robots to accept all files thrown at them.
  This will typically lead to errors and should only be used for debugging or combatting edge cases.

* `ignore_errors`: Ignore errors during specific phases of processing.

  Setting this to `["meta"]` will cause the Robot to ignore errors during metadata extraction.

  Setting this to `["execute"]` will cause the Robot to ignore errors during the main execution phase.

  Setting this to `true` is equivalent to `["meta", "execute"]` and will ignore errors in both phases.

* `use`: Specifies which Step(s) to use as input.

  * You can pick any names for Steps except `":original"` (reserved for user uploads handled by Transloadit)
  * You can provide several Steps as input with arrays:
    ```json
    {
      "use": [
        ":original",
        "encoded",
        "resized"
      ]
    }
    ```
  * You can also tag input Steps with `as` to pass semantic intent to robots:
    ```json
    {
      "use": [
        {
          "name": ":original",
          "as": "image"
        },
        {
          "name": ":original",
          "as": "mask"
        }
      ]
    }
    ```

  > [!Tip]
  > That's likely all you need to know about `use`, but you can view [Advanced use cases](/docs/topics/use-parameter.md).

* `url`: The URL of the web page to be converted. Optional, as you can also upload/import HTML files and pass it to this <dfn>Robot</dfn>.

* `format`: The format of the resulting image.

* `fullpage`: Determines if a screenshot of the full page should be taken or not.

  If set to `true`, the `height` parameter will not have any effect, as heights of websites vary. You can control the size of the resulting image somewhat, though, by setting the `width` parameter.

  If set to `false`, an image will be cropped from the top of the webpage according to your `width` and `height` parameters.

* `omit_background`: Determines whether to preserve a transparent background in HTML pages. Useful if you're generating artwork in HTML that you want to overlay on e.g. a video.

  The default of `false` fills transparent areas with a white background, for easier reading/printing.

  This parameter is only used when `format` is not `pdf`.

* `width`: The screen width that will be used, in pixels. Change this to change the  dimensions of the resulting image.

* `height`: The screen height that will be used, in pixels. By default this equals the length of the web page in pixels if `fullpage` is set to `true`. If `fullpage` is set to `false`, the height parameter takes effect and defaults to the value `768`.

* `delay`: The delay (in milliseconds) applied to allow the page and all of its JavaScript to render before taking the screenshot.

* `headers`: An object containing optional headers that will be passed along with the original request to the website. For example, this parameter can be used to pass along an authorization token along with the request.

* `wait_until`: The event to wait for before taking the screenshot. Used for loading Javascript, and images.

  See [Playwright's documentation](https://playwright.dev/docs/api/class-page#page-wait-for-load-state) for more information.