is this possible to get EPS save encoding (ie.. BINARY, ASCII, ASCII85)

The format of Photoshop EPS files is partially documented here:

http://www.adobe.com/devnet-apps/photoshop/fileformatashtml/#50577413_pgfId-1035096

Photoshop includes a comment in the EPS files it writes so that it is able to read them back in again. Third party programs that write pixel-based EPS files may want to include this comment in their EPS files, so Photoshop can read their files.

The comment must follow immediately after the %% comment block at the start of the file. The comment is:

%ImageData: <columns> <rows> <depth> <mode> <pad channels> <block size> <binary/hex> "<data start>"

<columns>: Width of the image in pixels.

<rows>: Height of the image in pixels.

<depth>: Number of bits per channel. Must be 1 or 8.

<mode>: Image mode. Bitmap/grayscale = 1; Lab = 2; RGB = 3; CMYK = 4.

<pad channels>: Number of other channels store in the file. Ignored when reading. Photoshop uses this to include a grayscale image that is printed on non-color PostScript printers.

<block size>:Number of bytes per row per channel. Will be either 1 or formula (below):

  1 = Data is interleaved.

  (columns*depth+7)/8 = Data is stored in line-interleaved format, or there is only one channel.

<binary/hex>:

  1 = Data is in binary format.

  2 = Data is in hex ascii format.

<data start>: Entire PostScript line immediately preceding the image data. This entire line should not occur elsewhere in the PostScript header code, but it may occur at part of a line.

Besides, some information about other values of <binary/hex> can be found here:

http://python.6.x6.nabble.com/Correctly-determine-image-size-of-a-Photoshop-EPS-td2096786.html

1 - binary

2 - ascii

3 - jpeg low quality

4 - jpeg medium quality

5 - jpeg high quality

6 - jpeg maximum quality

7 - ascii85

Here is a test script using this information:

function main ()
{
    function isPhotoshopEPSFile (f)
    {
        return (f.type === 'EPSF') || f.name.match (/\.eps$/i);
    }
    var epsFilter =
        (File.fs === "Macintosh") ?
            function (f) { return (f instanceof Folder) || isPhotoshopEPSFile (f) } :
            "Photoshop EPS Files:*.eps,All Files:*.*";
    var epsFile = File.openDialog ("Open Photoshop EPS file:", epsFilter);
    if (epsFile)
    {
        if (epsFile.open ("r"))
        {
            while (!epsFile.eof)
            {
                var line = epsFile.readln ();
                var found = line.match (/^%ImageData:\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/);
                if (found)
                {
                    var dataFormatIndex = found[7];
                    var dataFormats =
                    [
                        "Binary",
                        "ASCII",
                        "JPEG (low quality)",
                        "JPEG (medium quality)",
                        "JPEG (high quality)",
                        "JPEG (maximum quality)",
                        "ASCII85"
                    ];
                    alert (dataFormats[dataFormatIndex - 1]);
                    break;
                }
            }
            epsFile.close ();
        }
    }
}
main ();

HTH,

--Mikaeru