Constructor
func NewImageToImageClient(userName string, apiKey string) ImageToImageClient
Constructor for the PDFCrowd API client. Initialize a new instance of the conversion client with your PDFCrowd account credentials.
You must provide both your username and API key. This establishes the authenticated connection for all subsequent conversion operations.
- Parameters:
-
-
userName- Your username at PDFCrowd. -
apiKey- Your API key.
-
Conversion Input
func (client *ImageToImageClient) ConvertUrl(url string) ([]byte, error)
Convert an image from a URL.
Use this as the primary method for converting web content, online documents, or any publicly accessible URL to the desired output format. Returns the conversion result as a byte array for further processing or direct use.
- Parameter:
-
-
url- The address of the image to convert.- Constraint:
-
- Supported protocols are http:// and https://.
-
- Returns:
- []byte - Byte array containing the conversion output.
func (client *ImageToImageClient) ConvertUrlToStream(url string, outStream io.Writer) error
Convert an image from a URL and write the conversion result directly to an output stream.
Use this when you need to handle large conversion results, integrate with streaming pipelines, or build server applications that process conversions continuously.
- Parameters:
-
-
url- The address of the image to convert.- Constraint:
-
- Supported protocols are http:// and https://.
-
outStream(OutputStream) - The output stream that will contain the conversion output.
-
func (client *ImageToImageClient) ConvertUrlToFile(url string, filePath string) error
Convert an image from a URL and save the conversion result directly to a local file.
Use this for simple file-based workflows, batch processing, or when you need to persist conversion output to disk. The most straightforward method for URL-to-file conversions.
- Parameters:
-
-
url- The address of the image to convert.- Constraint:
-
- Supported protocols are http:// and https://.
-
filePath- The output file path.
-
func (client *ImageToImageClient) ConvertFile(file string) ([]byte, error)
Convert a local file to the desired output format.
Use this for processing files already on your system, converting uploaded documents, or batch processing local content. Returns the conversion result as a byte array for in-memory processing.
- Parameter:
-
-
file- The path to a local file to convert.
- Constraint:
-
- The file must exist and not be empty.
-
- Returns:
- []byte - Byte array containing the conversion output.
func (client *ImageToImageClient) ConvertFileToStream(file string, outStream io.Writer) error
Convert a local file and write the conversion result directly to an output stream.
Use this when working with large conversion results, integrating with streaming frameworks, or building applications that need direct stream-to-stream processing.
- Parameters:
-
-
file- The path to a local file to convert.
- Constraint:
-
- The file must exist and not be empty.
-
outStream(OutputStream) - The output stream that will contain the conversion output.
-
func (client *ImageToImageClient) ConvertFileToFile(file string, filePath string) error
Convert a local file and save the conversion result to another local file.
Use this for file-based batch processing, document transformation workflows, or when both input and output are file-based. The simplest method for file-to-file conversions.
- Parameters:
-
-
file- The path to a local file to convert.
- Constraint:
-
- The file must exist and not be empty.
-
filePath- The output file path.
-
func (client *ImageToImageClient) ConvertRawData(data []byte) ([]byte, error)
Convert raw binary data to the desired output format.
Use this for processing binary content, handling file uploads as byte arrays, or when working with data from external APIs. Provides maximum flexibility for binary data conversions.
- Parameter:
-
-
data(byte[]) - The raw content to be converted.
-
- Returns:
- []byte - Byte array with the output.
func (client *ImageToImageClient) ConvertRawDataToStream(data []byte, outStream io.Writer) error
Convert raw binary data and write the conversion result directly to an output stream.
Use this when handling large binary data with substantial conversion results, integrating with streaming systems, or building high-performance conversion services.
- Parameters:
-
-
data(byte[]) - The raw content to be converted. -
outStream(OutputStream) - The output stream that will contain the conversion output.
-
func (client *ImageToImageClient) ConvertRawDataToFile(data []byte, filePath string) error
Convert raw binary data and save the conversion result to a local file.
Use this for processing binary uploads and persisting the output, handling data from external sources, or when working with byte array inputs that need file-based storage.
- Parameters:
-
-
data(byte[]) - The raw content to be converted. -
filePath- The output file path.
-
func (client *ImageToImageClient) ConvertStream(inStream io.Reader) ([]byte, error)
Convert content from an input stream to the desired output format.
Use this when integrating with I/O pipelines, processing data from network streams or file handles, or when the source data is provided as a stream by your application.
- Parameter:
-
-
inStream(InputStream) - The input stream with source data.
-
- Returns:
- []byte - Byte array containing the conversion output.
func (client *ImageToImageClient) ConvertStreamToStream(inStream io.Reader, outStream io.Writer) error
Convert content from an input stream and write the conversion result to an output stream.
Use this when both input and output need to be streams, integrating with streaming frameworks, or building conversion services that process data in stream form throughout.
- Parameters:
-
-
inStream(InputStream) - The input stream with source data.
-
outStream(OutputStream) - The output stream that will contain the conversion output.
-
func (client *ImageToImageClient) ConvertStreamToFile(inStream io.Reader, filePath string) error
Convert content from an input stream and save the conversion result to a local file.
Use this when processing streaming uploads that need to be saved, handling network data sources with file-based output, or building services that accept stream input and produce file output.
- Parameters:
-
-
inStream(InputStream) - The input stream with source data.
-
filePath- The output file path.
-
Conversion Format
func (client *ImageToImageClient) SetOutputFormat(outputFormat string) *ImageToImageClient
The output file format.
- Parameter:
-
-
outputFormat- Allowed Values:
-
-
png -
jpg -
gif -
tiff -
bmp -
ico -
ppm -
pgm -
pbm -
pnm -
psb -
pct -
ras -
tga -
sgi -
sun -
webp
-
- Default:
-
png
-
Image Operations
Settings used for operations with images.
func (client *ImageToImageClient) SetResize(resize string) *ImageToImageClient
Scale the image to different dimensions. Accepts percentage values for proportional scaling or explicit pixel dimensions for absolute sizing.
- Parameter:
-
-
resize- The resize percentage or new image dimensions.- Default:
-
100%
-
- Examples:
-
-
Enlarge for high-res display:
SetResize("200%") -
Standard XGA screen resolution:
SetResize("1024x768")
-
Enlarge for high-res display:
func (client *ImageToImageClient) SetRotate(rotate string) *ImageToImageClient
Rotate the image by the specified angle in degrees. Positive values rotate clockwise, negative values counterclockwise.
- Parameter:
-
-
rotate- The rotation specified in degrees.
-
func (client *ImageToImageClient) SetCropAreaX(x string) *ImageToImageClient
Set the horizontal starting position of the crop area, measured from the left edge of the print area. Positive values offset inward from the left edge, negative values extend beyond the left boundary.
- Parameter:
-
-
x- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
- Default:
-
0px
-
- Examples:
-
-
Crop extends beyond left edge:
SetCropAreaX("-1in") -
Skip narrow border area:
SetCropAreaX("10mm")
-
Crop extends beyond left edge:
func (client *ImageToImageClient) SetCropAreaY(y string) *ImageToImageClient
Set the vertical starting position of the crop area, measured from the top edge of the print area. Positive values offset inward from the top edge, negative values extend beyond the top boundary.
- Parameter:
-
-
y- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
- Default:
-
0px
-
- Examples:
-
-
Crop extends beyond top edge:
SetCropAreaY("-1in") -
Skip narrow border area:
SetCropAreaY("10mm")
-
Crop extends beyond top edge:
func (client *ImageToImageClient) SetCropAreaWidth(width string) *ImageToImageClient
Set the horizontal extent of the crop area. Defines the width of the region to be converted. Minimum value is 1 inch.
- Parameter:
-
-
width- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
- Default:
-
The width of the print area.
-
- Examples:
-
-
Standard document crop width:
SetCropAreaWidth("8in") -
Full A4 page width crop:
SetCropAreaWidth("210mm")
-
Standard document crop width:
func (client *ImageToImageClient) SetCropAreaHeight(height string) *ImageToImageClient
Set the vertical extent of the crop area. Defines the height of the region to be converted. Minimum value is 1 inch.
- Parameter:
-
-
height- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
- Default:
-
The height of the print area.
-
- Examples:
-
-
Standard US Letter crop height:
SetCropAreaHeight("11in") -
Full A4 page height crop:
SetCropAreaHeight("297mm")
-
Standard US Letter crop height:
func (client *ImageToImageClient) SetCropArea(x string, y string, width string, height string) *ImageToImageClient
Define a rectangular region to convert by setting X/Y position and width/height simultaneously. Coordinates are relative to the print area's top-left corner.
- Parameters:
-
-
x- Set the horizontal starting position of the crop area, measured from the left edge of the print area. Positive values offset inward from the left edge, negative values extend beyond the left boundary.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
- Default:
-
0px
-
y- Set the vertical starting position of the crop area, measured from the top edge of the print area. Positive values offset inward from the top edge, negative values extend beyond the top boundary.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
- Default:
-
0px
-
width- Set the horizontal extent of the crop area. Defines the width of the region to be converted. Minimum value is 1 inch.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
- Default:
-
The width of the print area.
-
height- Set the vertical extent of the crop area. Defines the height of the region to be converted. Minimum value is 1 inch.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
- Default:
-
The height of the print area.
-
func (client *ImageToImageClient) SetRemoveBorders(value bool) *ImageToImageClient
Detect and remove solid-color borders surrounding the image content. Only removes borders that consist of a single consistent color.
- Parameter:
-
-
value(bool) - Set totrueto remove borders.- Default:
-
false
-
Canvas Setup
func (client *ImageToImageClient) SetCanvasSize(size string) *ImageToImageClient
Set the output canvas size. Use standard sizes (A4, Letter, A3, etc.) for printable output with consistent dimensions.
- Parameter:
-
-
size- Allowed Values:
-
-
A0 -
A1 -
A2 -
A3 -
A4 -
A5 -
A6 -
Letter
-
-
func (client *ImageToImageClient) SetCanvasWidth(width string) *ImageToImageClient
Set the output canvas width.
- Parameter:
-
-
width- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
- Examples:
-
-
A4 landscape / banner width:
SetCanvasWidth("297mm") -
US Letter standard width:
SetCanvasWidth("8.5in")
-
A4 landscape / banner width:
func (client *ImageToImageClient) SetCanvasHeight(height string) *ImageToImageClient
Set the output canvas height.
- Parameter:
-
-
height- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
- Examples:
-
-
Large poster canvas height:
SetCanvasHeight("420mm") -
US Letter standard height:
SetCanvasHeight("11in")
-
Large poster canvas height:
func (client *ImageToImageClient) SetCanvasDimensions(width string, height string) *ImageToImageClient
Set the output canvas dimensions. If no canvas size is specified, margins are applied as a border around the image.
- Parameters:
-
-
width- Set the output canvas width.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
height- Set the output canvas height.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
- Examples:
-
-
A4 portrait dimensions:
SetCanvasDimensions("210mm", "297mm") -
US Letter dimensions:
SetCanvasDimensions("8.5in", "11in") -
A3 portrait dimensions:
SetCanvasDimensions("297mm", "420mm")
-
A4 portrait dimensions:
func (client *ImageToImageClient) SetOrientation(orientation string) *ImageToImageClient
Set the output canvas orientation. Use portrait for vertical content, landscape for horizontal or wide content.
- Parameter:
-
-
orientation- Allowed Values:
-
-
landscape -
portrait
-
- Default:
-
portrait
-
func (client *ImageToImageClient) SetPosition(position string) *ImageToImageClient
Set the image position on the canvas. Center for balanced composition, or corner/edge positions for specific layouts.
- Parameter:
-
-
position- Allowed Values:
-
-
center -
top -
bottom -
left -
right -
top-left -
top-right -
bottom-left -
bottom-right
-
- Default:
-
center
-
func (client *ImageToImageClient) SetPrintCanvasMode(mode string) *ImageToImageClient
Set the mode to print the image on the canvas.
- Parameter:
-
-
mode- Allowed Values:
-
-
default— No image scaling. -
fit— Fit the image to the canvas with aspect ratio. -
stretch— Stretch the image to the canvas with no aspect ratio.
-
- Default:
-
default
-
func (client *ImageToImageClient) SetMarginTop(top string) *ImageToImageClient
Set the output canvas top margin.
- Parameter:
-
-
top- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
- Examples:
-
-
Wide margin for framing:
SetMarginTop("1in") -
Minimal margin for web images:
SetMarginTop("10mm")
-
Wide margin for framing:
func (client *ImageToImageClient) SetMarginRight(right string) *ImageToImageClient
Set the output canvas right margin.
- Parameter:
-
-
right- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
- Examples:
-
-
Wide margin for framing:
SetMarginRight("1in") -
Minimal margin for web images:
SetMarginRight("10mm")
-
Wide margin for framing:
func (client *ImageToImageClient) SetMarginBottom(bottom string) *ImageToImageClient
Set the output canvas bottom margin.
- Parameter:
-
-
bottom- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
- Examples:
-
-
Wide margin for framing:
SetMarginBottom("1in") -
Minimal margin for web images:
SetMarginBottom("10mm")
-
Wide margin for framing:
func (client *ImageToImageClient) SetMarginLeft(left string) *ImageToImageClient
Set the output canvas left margin.
- Parameter:
-
-
left- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
- Examples:
-
-
Wide margin for framing:
SetMarginLeft("1in") -
Minimal margin for web images:
SetMarginLeft("10mm")
-
Wide margin for framing:
func (client *ImageToImageClient) SetMargins(top string, right string, bottom string, left string) *ImageToImageClient
Set the output canvas margins. Create white space around the image for framing, borders, or print bleed.
- Parameters:
-
-
top- Set the output canvas top margin.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
right- Set the output canvas right margin.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
bottom- Set the output canvas bottom margin.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
left- Set the output canvas left margin.- Constraint:
-
- The value must be specified in inches 'in', millimeters 'mm', centimeters 'cm', pixels 'px', or points 'pt'.
-
func (client *ImageToImageClient) SetCanvasBackgroundColor(color string) *ImageToImageClient
The canvas background color in RGB or RGBA hexadecimal format. The color fills the entire canvas regardless of margins. If no canvas size is specified and the image format supports background (e.g. PDF, PNG), the background color is applied too.
- Parameter:
-
-
color- Constraint:
-
- The value must be in RRGGBB or RRGGBBAA hexadecimal format.
-
- Examples:
-
-
red color:
SetCanvasBackgroundColor("FF0000") -
green color:
SetCanvasBackgroundColor("00ff00") -
green color with 50% opacity:
SetCanvasBackgroundColor("00ff0080")
-
red color:
func (client *ImageToImageClient) SetDpi(dpi int) *ImageToImageClient
Set the DPI resolution of the input image. The DPI affects margin options specified in points too (e.g. 1 point is equal to 1 pixel in 96 DPI).
- Parameter:
-
-
dpi(int) - The DPI value.- Default:
-
96
-
- Example:
-
-
The DPI used for printers. 1 inch contains 300 points:
SetDpi(300)
-
The DPI used for printers. 1 inch contains 300 points:
Miscellaneous
func (client *ImageToImageClient) SetDebugLog(value bool) *ImageToImageClient
Turn on debug logging to troubleshoot conversion issues. Details about the conversion process, including resource loading, rendering steps, and error messages are stored in the debug log. Use this when conversions fail or produce unexpected results. The URL of the log can be obtained from the getDebugLogUrl method or available in conversion statistics.
- Parameter:
-
-
value(bool) - Set totrueto enable debug logging.- Default:
-
false
-
func (client *ImageToImageClient) GetDebugLogUrl() string
Get the URL of the debug log for the last conversion.
- Returns:
- string - The link to the debug log.
func (client *ImageToImageClient) GetRemainingCreditCount() int
Get the number of conversion credits available in your account. Use this to monitor your credit usage and implement alerts before running out of credits.
This method can only be called after a call to one of the convertXtoY methods.
The returned value can differ from the actual count if you run parallel conversions.
The special value 999999 is returned if the information is not available.
- Returns:
- int - The number of credits.
func (client *ImageToImageClient) GetConsumedCreditCount() int
Get the number of credits consumed by the last conversion. Use this to track costs per conversion, especially for complex documents or operations that may consume multiple credits.
- Returns:
- int - The number of credits.
func (client *ImageToImageClient) GetJobId() string
Get the unique job ID for the conversion. Use this to track conversions in your logs, correlate with debug logs, or reference specific conversions when contacting support.
- Returns:
- string - The unique job identifier.
func (client *ImageToImageClient) GetOutputSize() int
Get the size of the output document in bytes. Use this to check file sizes before delivery, implement size-based quotas, or optimize storage allocation.
- Returns:
- int - The count of bytes.
func (client *ImageToImageClient) GetVersion() string
Get the version details including API version, converter version, and client library version. Use this for debugging, logging, or ensuring compatibility when reporting issues.
- Returns:
- string - API version, converter version, and client version.
func (client *ImageToImageClient) SetTag(tag string) *ImageToImageClient
Tag the conversion with a custom value for tracking and analytics. Use this to categorize conversions by customer ID, document type, or business unit. The tag appears in conversion statistics. A value longer than 32 characters is cut off.
- Parameter:
-
-
tag- A string with the custom tag.
-
- Example:
-
-
Track job in analytics:
SetTag("client-1234")
-
Track job in analytics:
func (client *ImageToImageClient) SetHttpProxy(proxy string) *ImageToImageClient
A proxy server used by the conversion process for accessing the source URLs with HTTP scheme. This can help circumvent regional restrictions or provide limited access to your intranet.
- Parameter:
-
-
proxy- Constraint:
-
- The value must have format DOMAIN_OR_IP_ADDRESS:PORT.
-
- Examples:
-
-
Corporate proxy server:
SetHttpProxy("myproxy.com:8080") -
Direct IP proxy connection:
SetHttpProxy("113.25.84.10:33333")
-
Corporate proxy server:
func (client *ImageToImageClient) SetHttpsProxy(proxy string) *ImageToImageClient
A proxy server used by the conversion process for accessing the source URLs with HTTPS scheme. This can help circumvent regional restrictions or provide limited access to your intranet.
- Parameter:
-
-
proxy- Constraint:
-
- The value must have format DOMAIN_OR_IP_ADDRESS:PORT.
-
- Examples:
-
-
Secure proxy for HTTPS:
SetHttpsProxy("myproxy.com:443") -
Direct secure proxy IP:
SetHttpsProxy("113.25.84.10:44333")
-
Secure proxy for HTTPS:
API Client Options
func (client *ImageToImageClient) SetConverterVersion(version string) *ImageToImageClient
Set the converter version. Different versions may produce different output. Choose which one provides the best output for your case.
- Availability:
- API client >= 5.0.0. See versioning.
- Parameter:
-
-
version- The version identifier.- Allowed Values:
-
-
24.04— Version 24.04. -
20.10— Version 20.10. -
18.10— Version 18.10. -
latest— Version 20.10 is used.
-
- Default:
-
24.04
-
func (client *ImageToImageClient) SetUseHttp(value bool) *ImageToImageClient
Specify whether to use HTTP or HTTPS when connecting to the PDFCrowd API.
- Parameter:
-
-
value(bool) - Set totrueto use HTTP.- Default:
-
false
-
func (client *ImageToImageClient) SetClientUserAgent(agent string) *ImageToImageClient
Specify the User-Agent HTTP header that the client library will use when interacting with the API.
- Availability:
- API client >= 6.4.0 See versioning.
- Parameter:
-
-
agent- The user agent string.
-
func (client *ImageToImageClient) SetUserAgent(agent string) *ImageToImageClient
Set a custom user agent HTTP header. It can be useful if you are behind a proxy or a firewall.
- Parameter:
-
-
agent- The user agent string.- Default:
-
pdfcrowd_go_client/6.5.4 (https://pdfcrowd.com)
-
func (client *ImageToImageClient) SetProxy(host string, port int, userName string, password string) *ImageToImageClient
Specify an HTTP proxy that the API client library will use to connect to the internet.
- Parameters:
-
-
host- The proxy hostname. -
port(int) - The proxy port. -
userName- The username. -
password- The password.
-
func (client *ImageToImageClient) SetRetryCount(count int) *ImageToImageClient
Specify the number of automatic retries when a 502 or 503 HTTP status code is received. The status code indicates a temporary network issue. This feature can be disabled by setting to 0.
- Parameter:
-
-
count(int) - Number of retries.- Default:
-
1
-
- Example:
-
-
Retry failed requests three times:
SetRetryCount(3)
-
Retry failed requests three times: