advise to support ico

[Nyx2022]

Description

hello,i use AddPictureFromBytes to add an ico to a cell,but it return an error with "image: unknown format",can you support it

Additional context

No response

Validations

• Check that there isn't already an issue that requests the same feature to avoid creating a duplicate.

[xuri]

Thanks for your issue. I have added support for this. Please upgrade to the master branch code by go get github.com/xuri/excelize/v2@master, and this feature will be released on the next version. Now you can set insert ICO format image like this:

package main

import (
    "fmt"
    "image"
    "io"
    "os"

    "github.com/xuri/excelize/v2"
)

func main() {
    f := excelize.NewFile()
    defer func() {
        // Close the spreadsheet.
        if err := f.Close(); err != nil {
            fmt.Println(err)
        }
    }()
    imgFile, err := os.ReadFile("image.ico")
    if err != nil {
        fmt.Println(err)
    }
    decode := func(r io.Reader) (image.Image, error) { return nil, nil }
    decodeConfig := func(r io.Reader) (image.Config, error) {
        return image.Config{Height: 100, Width: 90}, nil
    }
    image.RegisterFormat("ico", "", decode, decodeConfig)

    if err := f.AddPictureFromBytes("Sheet1", "A2", &excelize.Picture{
        Extension: ".ico",
        File:      imgFile,
        Format:    &excelize.GraphicOptions{AltText: "ICO Image"},
    }); err != nil {
        fmt.Println(err)
        return
    }
    if err := f.SaveAs("Book1.xlsx"); err != nil {
        fmt.Println(err)
    }
}