PDF to PNG Tool Guide

Note：Before learning how to use different functions, we recommend that read the Request Workflow to know a basic PDF processing process. When using different functions, you can set their own special parameters when uploading files. Other basic steps are consistent.

PDF to PNG：

{
  "pageRanges": "1,2,3-5",
  "imageColorMode": "e_Color",
  "imageScaling": "1.0"
}

Required parameters

pageRanges: Specify page number conversion, starting from 1. Default is empty.

imageColorMode: Specifies the image color mode of the image file. e_Color: color mode; e_Gray: grayscale mode; e_Binary: black and white mode. The default is e_Color.

imageScaling: Specifies the image scaling ratio of the image file. Default is 1.0.

Setting Image Color Modes

Supported image color modes in ComPDFKit Conversion SDK include:

Color: Color mode, where the image effect is consistent with the original PDF page.

Gray: Grayscale mode.

Binary: Black and white mode, which applies binarization to the original effect.

Setting Image Scaling

The SDK supports setting image scaling. The default scaling is 1.0, which maintains the original PDF page size. If you want to double the image size, you can set ImageScaling to 2.0; similarly, to reduce the image size by half, set ImageScaling to 0.5.

Request Example:

Replace apiKey with the publicKey obtained from the dashboard, file with the file you want to convert, and language with your preferred interface error prompt language type.

curl

curl --location --request POST 'https://api-server.compdf.com/server/v2/process/pdf/png' \
--header 'x-api-key: apiKey' \
--header 'Accept: */*' \
--header 'Connection: keep-alive' \
--header 'Content-Type: multipart/form-data' \
--form 'file=@"file"' \
--form 'password="" \
--form 'parameter="{  \"pageRanges\": \"1,2,3-5\",  \"imageColorMode\": \"e_Color\", \"imageScaling\": \"1.0\"}"' \
--form 'language="1"'

java

import java.io.*;
import okhttp3.*;
public class main {
  public static void main(String []args) throws IOException{
    OkHttpClient client = new OkHttpClient().newBuilder()
      .build();
    MediaType mediaType = MediaType.parse("text/plain");
    RequestBody body = new MultipartBody.Builder().setType(MultipartBody.FORM)
      .addFormDataPart("file","{{file}}",
 RequestBody.create(MediaType.parse("application/octet-stream"),
                                          new File("<file>")))
      .addFormDataPart("language","{{language}}")
      .addFormDataPart("password","")
      .addFormDataPart("parameter","{  \"imageScaling\": \"1.0\"}")
       .build();
    Request request = new Request.Builder()
      .url("https://api-server.compdf.com/server/v2/process/pdf/png")
      .method("POST", body)
      .addHeader("x-api-key", "{{apiKey}}")
      .build();
    Response response = client.newCall(request).execute();
  }
}

Response Information:

A successful request returns an HTTP 200 OK status code and a JSON response body showing the order details.

Response type:application/json

Response Parameter	Data Type	Description
code	String	HTTP request status, "200" indicates success
message	String	Request message
data	Object	Return result
+taskId	String	Task ID
+taskFileNum	int	Number of files processed in the task
+taskSuccessNum	int	Number of files successfully processed in the task
+taskFailNum	int	Number of files failed in the task
+taskStatus	String	Task status
+assetTypeId	int	Used asset type ID
+taskCost	int	Task cost
+taskTime	int	Task duration
+sourceType	String	Original format
+targetType	String	Target format
+fileInfoDTOList	Array	Task file information
++fileKey	String	File key
++taskId	String	Task ID
++fileName	String	Original file name
++downFileName	String	Download file name
++fileUrl	String	Original file URL
++downloadUrl	String	Processed result file download URL
++sourceType	String	Original format
++targetType	String	Target format
++fileSize	int	File size
++convertSize	int	Processed result file size
++convertTime	int	Processing time
++status	String	File processing status
++failureCode	String	File processing failure error code
++failureReason	String	File processing failure description
++fileParameter	String	Processing parameter

Response Example:

"code": "200",
"msg": "success",
"data": {
    "taskId": "f416dbcf-0c10-4f93-ab9e-a835c1f5dba1",
    "taskFileNum": 1,
    "taskSuccessNum": 1,
    "taskFailNum": 0,
    "taskStatus": "<taskStatus>",
    "assetTypeId": 0,
    "taskCost": 1,
    "taskTime": 1,
    "sourceType": "<sourceType>",
    "targetType": "<targetType>",
    "fileInfoDTOList": [
      {
        "fileKey": "<fileKey>",
        "taskId": "<taskId>",
        "fileName": "<fileName>",
        "downFileName": "<downFileName>",
        "fileUrl": "<fileUrl>",
        "downloadUrl": "<downloadUrl>",
        "sourceType": "<sourceType>",
        "targetType": "<targetType>",
        "fileSize": 24475,
        "convertSize": 6922,
        "convertTime": 8,
        "status": "<status>",
        "failureCode": "",
        "failureReason": "",
        "fileParameter": "<fileParameter>"
      }
    ]
}

Result:

File Type	Description
.zip	The image file zip after the transfer process is completed

Asynchronous Request

If you need to use the file asynchronous processing flow, please read the Asynchronous Request Instructions.