diff options
Diffstat (limited to 'src/cmd/jpg/writepng.c')
| -rw-r--r-- | src/cmd/jpg/writepng.c | 38 |
1 files changed, 19 insertions, 19 deletions
diff --git a/src/cmd/jpg/writepng.c b/src/cmd/jpg/writepng.c index e280a9cc..3b63bb7f 100644 --- a/src/cmd/jpg/writepng.c +++ b/src/cmd/jpg/writepng.c @@ -1,7 +1,7 @@ -// based on PNG 1.2 specification, July 1999 (see also rfc2083) -// Alpha is not supported yet because of lack of industry acceptance and -// because Plan9 Image uses premultiplied alpha, so png can't be lossless. -// Only 24bit color supported, because 8bit may as well use GIF. +/* based on PNG 1.2 specification, July 1999 (see also rfc2083) */ +/* Alpha is not supported yet because of lack of industry acceptance and */ +/* because Plan9 Image uses premultiplied alpha, so png can't be lossless. */ +/* Only 24bit color supported, because 8bit may as well use GIF. */ #include <u.h> #include <libc.h> @@ -13,22 +13,22 @@ #include "imagefile.h" enum{ IDATSIZE = 20000, - FilterNone = 0, + FilterNone = 0 }; typedef struct ZlibR{ uchar *data; int width; int nrow, ncol; - int row, col; // next pixel to send + int row, col; /* next pixel to send */ int pixwid; } ZlibR; typedef struct ZlibW{ Biobuf *bo; uchar *buf; - uchar *b; // next place to write - uchar *e; // past end of buf + uchar *b; /* next place to write */ + uchar *e; /* past end of buf */ } ZlibW; static ulong *crctab; @@ -68,11 +68,11 @@ zread(void *va, void *buf, int n) int nrow = z->nrow; int ncol = z->ncol; uchar *b = buf, *e = b+n, *img; - int pixels; // number of pixels in row that can be sent now + int pixels; /* number of pixels in row that can be sent now */ int i, a, pixwid; pixwid = z->pixwid; - while(b+pixwid <= e){ // loop over image rows + while(b+pixwid <= e){ /* loop over image rows */ if(z->row >= nrow) break; if(z->col==0) @@ -129,7 +129,7 @@ zwrite(void *va, void *buf, int n) uchar *b = buf, *e = b+n; int m; - while(b < e){ // loop over IDAT chunks + while(b < e){ /* loop over IDAT chunks */ m = z->e - z->b; if(m > e - b) m = e - b; @@ -190,15 +190,15 @@ memwritepng(Biobuf *bo, Memimage *r, ImageInfo *II) deflateinit(); Bwrite(bo, PNGmagic, sizeof PNGmagic); - // IHDR chunk + /* IHDR chunk */ h = buf; put4(h, ncol); h += 4; put4(h, nrow); h += 4; - *h++ = 8; // bit depth = 24 bit per pixel - *h++ = rgb->chan==BGR24 ? 2 : 6; // color type = rgb - *h++ = 0; // compression method = deflate - *h++ = 0; // filter method - *h++ = 0; // interlace method = no interlace + *h++ = 8; /* bit depth = 24 bit per pixel */ + *h++ = rgb->chan==BGR24 ? 2 : 6; /* color type = rgb */ + *h++ = 0; /* compression method = deflate */ + *h++ = 0; /* filter method */ + *h++ = 0; /* interlace method = no interlace */ chunk(bo, "IHDR", buf, h-buf); tm = gmtime(time(0)); @@ -220,12 +220,12 @@ memwritepng(Biobuf *bo, Memimage *r, ImageInfo *II) if(II->fields_set & II_COMMENT){ strncpy((char*)buf, "Comment", sizeof buf); - n = strlen((char*)buf)+1; // leave null between Comment and text + n = strlen((char*)buf)+1; /* leave null between Comment and text */ strncpy((char*)(buf+n), II->comment, sizeof buf - n); chunk(bo, "tEXt", buf, n+strlen((char*)buf+n)); } - // image chunks + /* image chunks */ zr.nrow = nrow; zr.ncol = ncol; zr.width = rgb->width * sizeof(ulong); |