Pillow/src/libImaging/EpsEncode.c

/*
 * The Python Imaging Library.
 * $Id$
 *
 * encoder for EPS hex data
 *
 * history:
 * 96-04-19 fl created
 * 96-06-27 fl don't drop last block of encoded data
 *
 * notes:
 * FIXME: rename to HexEncode.c ??
 *
 * Copyright (c) Fredrik Lundh 1996.
 * Copyright (c) Secret Labs AB 1997.
 *
 * See the README file for information on usage and redistribution.
 */


#include "Imaging.h"


int
ImagingEpsEncode(Imaging im, ImagingCodecState state, UINT8* buf, int bytes)
{
    enum { HEXBYTE=1, NEWLINE };
    const char *hex = "0123456789abcdef";

    UINT8* ptr = buf;
    UINT8* in, i;

    if (!state->state) {
        state->state = HEXBYTE;
        state->xsize *= im->pixelsize; /* Hack! */
    }

    in = (UINT8*) im->image[state->y];

    for (;;) {

        if (state->state == NEWLINE) {
            if (bytes < 1) {
                break;
            }
            *ptr++ = '\n';
            bytes--;
            state->state = HEXBYTE;
        }

        if (bytes < 2) {
            break;
        }

        i = in[state->x++];
        *ptr++ = hex[(i>>4)&15];
        *ptr++ = hex[i&15];
        bytes -= 2;

        /* Skip junk bytes */
        if (im->bands == 3 && (state->x & 3) == 3) {
            state->x++;
        }

        if (++state->count >= 79/2) {
            state->state = NEWLINE;
            state->count = 0;
        }

        if (state->x >= state->xsize) {
            state->x = 0;
            if (++state->y >= state->ysize) {
                state->errcode = IMAGING_CODEC_END;
                break;
            }
            in = (UINT8*) im->image[state->y];
        }

    }

    return ptr - buf;

}