diff options
Diffstat (limited to 'filter/rle.c')
| -rw-r--r-- | filter/rle.c | 237 |
1 files changed, 0 insertions, 237 deletions
diff --git a/filter/rle.c b/filter/rle.c deleted file mode 100644 index 921e470a..00000000 --- a/filter/rle.c +++ /dev/null @@ -1,237 +0,0 @@ -#include <fitz.h> - -/* TODO: rewrite! - * make it non-optimal or something, - * just not this horrid mess... - */ - -#define noDEBUG - -typedef struct fz_rle_s fz_rle; - -struct fz_rle_s -{ - fz_filter super; - int reclen; - int curlen; - int state; - int run; - unsigned char buf[128]; -}; - -enum { - ZERO, - ONE, - DIFF, - SAME, - END -}; - -fz_error * -fz_newrle(fz_filter **fp, fz_obj *params) -{ - FZ_NEWFILTER(fz_rle, enc, rle); - - if (params) - enc->reclen = fz_toint(params); - else - enc->reclen = 0; - - enc->curlen = 0; - enc->state = ZERO; - enc->run = 0; - - return nil; -} - -void -fz_droprle(fz_filter *enc) -{ -} - -static fz_error * -putone(fz_rle *enc, fz_buffer *in, fz_buffer *out) -{ - if (out->wp + 2 >= out->ep) - return fz_ioneedout; - -#ifdef DEBUG -fprintf(stderr, "one '%c'\n", enc->buf[0]); -#endif - - *out->wp++ = 0; - *out->wp++ = enc->buf[0]; - - return nil; -} - -static fz_error * -putsame(fz_rle *enc, fz_buffer *in, fz_buffer *out) -{ - if (out->wp + enc->run >= out->ep) - return fz_ioneedout; - -#ifdef DEBUG -fprintf(stderr, "same %d x '%c'\n", enc->run, enc->buf[0]); -#endif - - *out->wp++ = 257 - enc->run; - *out->wp++ = enc->buf[0]; - return nil; -} - -static fz_error * -putdiff(fz_rle *enc, fz_buffer *in, fz_buffer *out) -{ - int i; - if (out->wp + enc->run >= out->ep) - return fz_ioneedout; - -#ifdef DEBUG -fprintf(stderr, "diff %d\n", enc->run); -#endif - - *out->wp++ = enc->run - 1; - for (i = 0; i < enc->run; i++) - *out->wp++ = enc->buf[i]; - return nil; -} - -static fz_error * -puteod(fz_rle *enc, fz_buffer *in, fz_buffer *out) -{ - if (out->wp + 1 >= out->ep) - return fz_ioneedout; - -#ifdef DEBUG -fprintf(stderr, "eod\n"); -#endif - - *out->wp++ = 128; - return nil; -} - -static fz_error * -savebuf(fz_rle *enc, fz_buffer *in, fz_buffer *out) -{ - switch (enc->state) - { - case ZERO: return nil; - case ONE: return putone(enc, in, out); - case SAME: return putsame(enc, in, out); - case DIFF: return putdiff(enc, in, out); - case END: return puteod(enc, in, out); - default: assert(!"invalid state in rle"); return nil; - } -} - -fz_error * -fz_processrle(fz_filter *filter, fz_buffer *in, fz_buffer *out) -{ - fz_rle *enc = (fz_rle*)filter; - fz_error *error; - unsigned char c; - - while (1) - { - - if (enc->reclen && enc->curlen == enc->reclen) { - error = savebuf(enc, in, out); - if (error) return error; -#ifdef DEBUG -fprintf(stderr, "--record--\n"); -#endif - enc->state = ZERO; - enc->curlen = 0; - } - - if (in->rp == in->wp) { - if (in->eof) { - if (enc->state != END) { - error = savebuf(enc, in, out); - if (error) return error; - } - enc->state = END; - } - else - return fz_ioneedin; - } - - c = *in->rp; - - switch (enc->state) - { - case ZERO: - enc->state = ONE; - enc->run = 1; - enc->buf[0] = c; - break; - - case ONE: - enc->state = DIFF; - enc->run = 2; - enc->buf[1] = c; - break; - - case DIFF: - /* out of space */ - if (enc->run == 128) { - error = putdiff(enc, in, out); - if (error) return error; - - enc->state = ONE; - enc->run = 1; - enc->buf[0] = c; - } - - /* run of three that are the same */ - else if ((enc->run > 1) && - (c == enc->buf[enc->run - 1]) && - (c == enc->buf[enc->run - 2])) - { - if (enc->run >= 3) { - enc->run -= 2; /* skip prev two for diff run */ - error = putdiff(enc, in, out); - if (error) return error; - } - - enc->state = SAME; - enc->run = 3; - enc->buf[0] = c; - } - - /* keep on collecting */ - else { - enc->buf[enc->run++] = c; - } - break; - - case SAME: - if (enc->run == 128 || c != enc->buf[0]) { - error = putsame(enc, in, out); - if (error) return error; - - enc->state = ONE; - enc->run = 1; - enc->buf[0] = c; - } - else { - enc->run ++; - } - break; - - case END: - error = puteod(enc, in, out); - if (error) return error; - - out->eof = 1; - return fz_iodone; - } - - in->rp ++; - - enc->curlen ++; - - } -} - |