]> git.sesse.net Git - qscale/blobdiff - qscale.c
Invert directions again, increasing speed but adding bugs.
[qscale] / qscale.c
index 042d3411a110f5464e218a3ef8c4b55f0af66ca8..8fecd666a972b1fad7a35b302dc5f8445677aca0 100644 (file)
--- a/qscale.c
+++ b/qscale.c
@@ -2,30 +2,9 @@
 #include <math.h>
 #include <string.h>
 #include <stdlib.h>
+#include "jpeglib.h"
 
-#define CACHE_LINE_FACTOR 1
-
-void myreadline(char *buf)
-{
-       char *ptr;
-
-       if (fgets(buf, 256, stdin) == NULL) {
-               fprintf(stderr, "Premuture EOF\n");
-               exit(1);
-       }
-
-       if (strlen(buf) == 0) {
-               return;
-       }
-
-       ptr = &buf[strlen(buf) - 1];
-       if (*ptr == '\n') {
-               *ptr-- = 0;
-               if (*ptr == '\r') {
-                       *ptr = 0;
-               }
-       }
-}
+#define CACHE_LINE_FACTOR 8
 
 double sinc(double x)
 {
@@ -52,7 +31,7 @@ struct pix_desc {
        unsigned startcoeff;
 };
 
-void hscale(float *pix, unsigned char *npix, unsigned w, unsigned h, unsigned nw)
+void hscale(float *pix, unsigned char *npix, unsigned w, unsigned h, unsigned nw, unsigned dstride)
 {
        struct pix_desc *pd = (struct pix_desc *)malloc(nw * sizeof(struct pix_desc));
        int size_coeffs = 8;
@@ -98,12 +77,12 @@ void hscale(float *pix, unsigned char *npix, unsigned w, unsigned h, unsigned nw
        
        for (y = 0; y < h; ++y) {
                float *sptr = pix + y*w;
-               unsigned char *dptr = npix + y*nw;
+               unsigned char *dptr = npix + y*dstride;
+               unsigned char ch = 0;
                for (x = 0; x < nw; ++x) {
                        float acc = 0.0;
                        float *cf = &coeffs[pd[x].startcoeff];
                        unsigned sx;
-                       unsigned char ch;
                        
                        for (sx = pd[x].start; sx <= pd[x].end; ++sx) {
                                acc += sptr[sx] * *cf++;
@@ -117,10 +96,13 @@ void hscale(float *pix, unsigned char *npix, unsigned w, unsigned h, unsigned nw
                                ch = (unsigned char)acc;
                        *dptr++ = ch;
                }
+               for ( ; x < dstride; ++x) {
+                       *dptr++ = ch;
+               }
        }
 }
 
-void vscale(unsigned char *pix, float *npix, unsigned w, unsigned h, unsigned nh)
+void vscale(unsigned char *pix, float *npix, unsigned w, unsigned h, unsigned nh, unsigned dstride)
 {
        struct pix_desc *pd = (struct pix_desc *)malloc(nh * sizeof(struct pix_desc));
        int size_coeffs = 8;
@@ -177,6 +159,7 @@ void vscale(unsigned char *pix, float *npix, unsigned w, unsigned h, unsigned nh
                        unsigned sy;
                        
                        for (sy = pd[y].start; sy <= pd[y].end; ++sy) {
+                               //asm volatile ("prefetcht0 %0" :: "m" (sptr[(sy+1) * w]));
                                for (i = 0; i < CACHE_LINE_FACTOR; ++i) {
                                        acc[i] += sptr[sy * w + i] * *cf;
                                }
@@ -186,7 +169,7 @@ void vscale(unsigned char *pix, float *npix, unsigned w, unsigned h, unsigned nh
                        for (i = 0; i < CACHE_LINE_FACTOR; ++i) {
                                dptr[i] = acc[i];
                        }
-                       dptr += w;
+                       dptr += dstride;
                }
        }
        for (x = (x/CACHE_LINE_FACTOR)*CACHE_LINE_FACTOR; x < w; ++x) {
@@ -205,74 +188,151 @@ void vscale(unsigned char *pix, float *npix, unsigned w, unsigned h, unsigned nh
                        }
 
                        *dptr = acc;
-                       dptr += w;
+                       dptr += dstride;
                }
        }
 }
 
-int main(void)
+int main(int argc, char **argv)
 {
-       unsigned w, h;
-       unsigned nw = 600, nh = 400;
-       //unsigned nw = 3504, nh = 2336;
-       char buf[256];
-       unsigned char *pix;
-       float *npix;
-       unsigned char *npix2;
-
-       myreadline(buf);
-       if (strcmp(buf, "P5") != 0) {
-               fprintf(stderr, "Error: Not a PGM file\n");
-               exit(1);
-       }
-       myreadline(buf);  /* comment */
-       myreadline(buf);
+       unsigned nominal_w = atoi(argv[1]);
+       unsigned nominal_h = atoi(argv[2]);
+
+       unsigned samp_h0 = 2, samp_v0 = 2;
+       unsigned samp_h1 = 1, samp_v1 = 1;
+       unsigned samp_h2 = 1, samp_v2 = 1;
+       unsigned max_samp_h = 2, max_samp_v = 2;
+
+       unsigned nw0 = nominal_w * samp_h0 / max_samp_h, nh0 = nominal_h * samp_v0 / max_samp_v;
+       unsigned nw1 = nominal_w * samp_h1 / max_samp_h, nh1 = nominal_h * samp_v1 / max_samp_v;
+       unsigned nw2 = nominal_w * samp_h2 / max_samp_h, nh2 = nominal_h * samp_v2 / max_samp_v;
+
+       unsigned stride0 = (nw0 + DCTSIZE-1) & ~(DCTSIZE-1);
+       unsigned stride1 = (nw1 + DCTSIZE-1) & ~(DCTSIZE-1);
+       unsigned stride2 = (nw2 + DCTSIZE-1) & ~(DCTSIZE-1);
+
+       struct jpeg_decompress_struct dinfo;
+       struct jpeg_error_mgr jerr;
+       dinfo.err = jpeg_std_error(&jerr);
+       jpeg_create_decompress(&dinfo);
+       jpeg_stdio_src(&dinfo, stdin);
+       jpeg_read_header(&dinfo, TRUE);
+       dinfo.raw_data_out = TRUE;
+       jpeg_start_decompress(&dinfo);
+
+       fprintf(stderr, "Scaling using Lanczos filter:\n");
+       fprintf(stderr, "  Y component: %ux%u -> %ux%u\n", dinfo.comp_info[0].width_in_blocks * DCTSIZE, dinfo.comp_info[0].height_in_blocks * DCTSIZE, nw0, nh0);
+       fprintf(stderr, "  Cb component: %ux%u -> %ux%u\n", dinfo.comp_info[1].width_in_blocks * DCTSIZE, dinfo.comp_info[1].height_in_blocks * DCTSIZE, nw1, nh1);
+       fprintf(stderr, "  Cr component: %ux%u -> %ux%u\n", dinfo.comp_info[2].width_in_blocks * DCTSIZE, dinfo.comp_info[2].height_in_blocks * DCTSIZE, nw2, nh2);
+
+       JSAMPLE *data_y  = (JSAMPLE*)malloc(dinfo.comp_info[0].height_in_blocks * dinfo.comp_info[0].width_in_blocks * DCTSIZE * DCTSIZE);
+       JSAMPLE *data_cb = (JSAMPLE*)malloc(dinfo.comp_info[1].height_in_blocks * dinfo.comp_info[1].width_in_blocks * DCTSIZE * DCTSIZE);
+       JSAMPLE *data_cr = (JSAMPLE*)malloc(dinfo.comp_info[2].height_in_blocks * dinfo.comp_info[2].width_in_blocks * DCTSIZE * DCTSIZE);
+       JSAMPLE *data_ny, *data_ncb, *data_ncr;
+
+       int total_lines = 0, blocks = 0;
+       while (total_lines < dinfo.comp_info[0].height_in_blocks * DCTSIZE) {
+               unsigned max_lines = dinfo.max_v_samp_factor * DCTSIZE;
+
+               JSAMPROW y_row_ptrs[max_lines];
+               JSAMPROW cb_row_ptrs[max_lines];
+               JSAMPROW cr_row_ptrs[max_lines];
+               JSAMPROW* ptrs[] = { y_row_ptrs, cb_row_ptrs, cr_row_ptrs };
+               int i;
+
+               for (i = 0; i < max_lines; ++i) {
+                       y_row_ptrs[i]  = data_y  + (i+blocks*DCTSIZE*dinfo.comp_info[0].v_samp_factor) * dinfo.comp_info[0].width_in_blocks * DCTSIZE;
+                       cb_row_ptrs[i] = data_cb + (i+blocks*DCTSIZE*dinfo.comp_info[1].v_samp_factor) * dinfo.comp_info[1].width_in_blocks * DCTSIZE;
+                       cr_row_ptrs[i] = data_cr + (i+blocks*DCTSIZE*dinfo.comp_info[2].v_samp_factor) * dinfo.comp_info[2].width_in_blocks * DCTSIZE;
+               }
+               
+               total_lines += max_lines;
+               ++blocks;
 
-       if (sscanf(buf, "%u %u", &w, &h) != 2) {
-               fprintf(stderr, "Error: Expected width/height\n");
-               exit(1);
+               if (jpeg_read_raw_data(&dinfo, ptrs, max_lines) == 0)
+                       break;
        }
 
-       myreadline(buf);
-       if (strcmp(buf, "255") != 0) {
-               fprintf(stderr, "Error: Expected 8-bit\n");
-               exit(1);
+       {
+               float *npix = (float*)malloc(dinfo.comp_info[0].width_in_blocks * DCTSIZE * nh0 * sizeof(float));       
+               vscale(data_y, npix, dinfo.comp_info[0].width_in_blocks * DCTSIZE, dinfo.comp_info[0].height_in_blocks * DCTSIZE, nh0, dinfo.comp_info[0].width_in_blocks * DCTSIZE);
+               data_ny = (unsigned char *)malloc(nw0 * stride0);
+               hscale(npix, data_ny, dinfo.comp_info[0].width_in_blocks * DCTSIZE, nh0, nw0, stride0);
+               free(npix);
        }
-
-       pix = (unsigned char *)malloc(w * h);
-       if (pix == NULL) {
-               perror("malloc");
-               exit(1);
+       {
+               float *npix = (float*)malloc(dinfo.comp_info[1].width_in_blocks * DCTSIZE * nh1 * sizeof(float));       
+               vscale(data_cr, npix, dinfo.comp_info[1].width_in_blocks * DCTSIZE, dinfo.comp_info[1].height_in_blocks * DCTSIZE, nh1, dinfo.comp_info[1].width_in_blocks * DCTSIZE);
+               data_ncr = (unsigned char *)malloc(nw1 * stride1);
+               hscale(npix, data_ncr, dinfo.comp_info[1].width_in_blocks * DCTSIZE, nh1, nw1, stride1);
+               free(npix);
        }
-
-       if (fread(pix, w*h, 1, stdin) != 1) {
-               fprintf(stderr, "Error: Short read\n");
-               exit(1);
+       {
+               float *npix = (float*)malloc(dinfo.comp_info[2].width_in_blocks * DCTSIZE * nh2 * sizeof(float));       
+               vscale(data_cb, npix, dinfo.comp_info[2].width_in_blocks * DCTSIZE, dinfo.comp_info[2].height_in_blocks * DCTSIZE, nh2, dinfo.comp_info[2].width_in_blocks * DCTSIZE);
+               data_ncb = (unsigned char *)malloc(nw2 * stride2);
+               hscale(npix, data_ncb, dinfo.comp_info[2].width_in_blocks * DCTSIZE, nh2, nw2, stride2);
+               free(npix);
        }
+       jpeg_destroy_decompress(&dinfo);
        
-       npix = (float *)malloc(sizeof(float) * nw * h);
-       if (npix == NULL) {
-               perror("malloc");
-               exit(1);
-       }
-       npix2 = (unsigned char *)malloc(nw * nh);
-       if (npix2 == NULL) {
-               perror("malloc");
-               exit(1);
-       }
-
-       vscale(pix, npix, w, h, nh);
-       hscale(npix, npix2, w, nh, nw);
-
-       printf("P5\n# COMMENT: Made by qscale\n%u %u\n255\n", nw, nh);
-       {
-               int y, x;
-               for (y = 0; y < nh; ++y) {
-                       for (x = 0; x < nw; ++x) {
-                               putchar(npix2[y * nw + x]);
-                       }
+       struct jpeg_compress_struct cinfo;
+       cinfo.err = jpeg_std_error(&jerr);
+       jpeg_create_compress(&cinfo);
+       jpeg_stdio_dest(&cinfo, stdout);
+       cinfo.input_components = 3;
+       jpeg_set_defaults(&cinfo);
+       jpeg_set_quality(&cinfo, 85, FALSE);
+       cinfo.image_width = nominal_w;
+       cinfo.image_height = nominal_h;
+       cinfo.raw_data_in = TRUE;
+       jpeg_set_colorspace(&cinfo, JCS_YCbCr);
+       cinfo.comp_info[0].h_samp_factor = samp_h0;
+       cinfo.comp_info[0].v_samp_factor = samp_v0;
+       cinfo.comp_info[1].h_samp_factor = samp_h1;
+       cinfo.comp_info[1].v_samp_factor = samp_v1;
+       cinfo.comp_info[2].h_samp_factor = samp_h2;
+       cinfo.comp_info[2].v_samp_factor = samp_v2;
+       jpeg_start_compress(&cinfo, TRUE);
+
+       total_lines = 0;
+       blocks = 0;
+       while (total_lines < cinfo.comp_info[0].height_in_blocks * DCTSIZE) {
+               unsigned max_lines = cinfo.max_v_samp_factor * DCTSIZE;
+
+               JSAMPROW y_row_ptrs[max_lines];
+               JSAMPROW cb_row_ptrs[max_lines];
+               JSAMPROW cr_row_ptrs[max_lines];
+               JSAMPROW* ptrs[] = { y_row_ptrs, cb_row_ptrs, cr_row_ptrs };
+               int i;
+
+               for (i = 0; i < max_lines; ++i) {
+                       // simple edge extension
+                       int yline = i + blocks*DCTSIZE*cinfo.comp_info[0].v_samp_factor;
+                       if (yline > nh0 - 1)
+                               yline = nh0 - 1;
+
+                       int cbline = i + blocks*DCTSIZE*cinfo.comp_info[1].v_samp_factor;
+                       if (cbline > nh1 - 1)
+                               cbline = nh1 - 1;
+
+                       int crline = i + blocks*DCTSIZE*cinfo.comp_info[2].v_samp_factor;
+                       if (crline > nh2 - 1)
+                               crline = nh2 - 1;
+
+                       y_row_ptrs[i]  = data_ny  + yline * stride0;
+                       cb_row_ptrs[i] = data_ncb + cbline * stride1;
+                       cr_row_ptrs[i] = data_ncr + crline * stride2;
                }
+               
+               total_lines += max_lines;
+               ++blocks;
+
+               jpeg_write_raw_data(&cinfo, ptrs, max_lines);
        }
+       jpeg_finish_compress(&cinfo);
+       jpeg_destroy_compress(&cinfo);
 
        return 0;
 }
+