]> git.sesse.net Git - qscale/blobdiff - qscale.c
Add support for grayscale JPEGs, although in a quite ugly way.
[qscale] / qscale.c
index ee70208c28e5307511324c73f6a3800084cb6ad8..6da1b390ab5ca46616c1dea74a10d96082a4c455 100644 (file)
--- a/qscale.c
+++ b/qscale.c
+/*
+ * qscale: Quick, high-quality JPEG-to-JPEG scaler.
+ * Copyright (C) 2008 Steinar H. Gunderson <sgunderson@bigfoot.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
 #include <stdio.h>
-#include <malloc.h>
-#include <math.h>
-#include <string.h>
 #include <stdlib.h>
-#include "jpeglib.h"
-
-#define CACHE_LINE_FACTOR 16
-
-#ifndef M_PI
-#define M_PI 3.14159265358979323846264
-#endif
-
-double sinc(double x)
-{
-       static const double cutoff = 1.220703668e-4;  /* sqrt(sqrt(eps)) */
-
-       if (abs(x) < cutoff) {
-               /* For small |x|, use Taylor series instead */
-               const double x2 = x * x;
-               const double x4 = x2 * x2;
-
-               return 1.0 - x2 / 6.0 + x4 / 120.0;
-       } else {
-               return sin(x) / x;
-       }
-}
-
-double lanczos_tap(double x)
-{
-       if (x < -3.0 || x > 3.0)
-               return 0.0;
-       if (x < 0.0)
-               return sinc(-x*M_PI) * sinc(-x*M_PI / 3.0);
-       else
-               return sinc(x*M_PI) * sinc(x*M_PI / 3.0);
-}
-
-
-struct pix_desc {
-       unsigned start, end;
-       unsigned startcoeff;
-};
-
-void hscale(float *pix, unsigned char *npix, unsigned w, unsigned h, unsigned nw, unsigned sstride, unsigned dstride)
-{
-       struct pix_desc *pd = (struct pix_desc *)malloc(nw * sizeof(struct pix_desc));
-       int size_coeffs = 8;
-       float *coeffs = (float *)malloc(size_coeffs * sizeof(float));
-       int num_coeffs = 0;
-       int x, y;
-       double sf = (double)w / (double)nw;
-       double support = (w > nw) ? (3.0 * sf) : (3.0 / sf);
-
-       /* calculate the filter */
-       for (x = 0; x < nw; ++x) {
-               int start = ceil(x * sf - support);
-               int end = floor(x * sf + support);
-               int sx;
-               double sum = 0.0;
-
-               if (start < 0) {
-                       start = 0;
-               }
-               if (end > w - 1) {
-                       end = w - 1;
-               }
-
-               /* round up so we get a multiple of four for the SSE code */
-               int num = (end - start + 1);
-               if (num % 4 != 0) {
-                       /* prefer aligning it if possible */
-                       if (start % 4 != 0 && start % 4 <= num % 4) {
-                               num += start % 4;
-                               start -= start % 4;
-                       }
-                       if (num % 4 != 0) {
-                               end += 4 - (num % 4);
-                       }
-               }
-
-               pd[x].start = start;
-               pd[x].end = end;
-               pd[x].startcoeff = num_coeffs;
-
-               for (sx = start; sx <= end; ++sx) {
-                       double nd = (w > nw) ? (sx/sf - x) : (sx - x*sf);
-                       double f = lanczos_tap(nd);
-                       if (num_coeffs == size_coeffs) {
-                               size_coeffs <<= 1;
-                               coeffs = (float *)realloc(coeffs, size_coeffs * sizeof(float));
-                       }
-
-                       coeffs[num_coeffs++] = f;
-                       sum += f;
-               }
-
-               for (sx = start; sx <= end; ++sx) {
-                       coeffs[pd[x].startcoeff + sx - start] /= sum;
-               }
-       }
-
-       for (y = 0; y < h; ++y) {
-               float *sptr = pix + y*sstride;
-               unsigned char *dptr = npix + y*dstride;
-               unsigned char ch;
-               for (x = 0; x < nw; ++x) {
-                       int result;
-                       float acc;
-                       long tmp;
-                       static const float low = 0.0, high = 255.0;
-                       __asm__ (
-                               "pxor %1, %1               \n"
-                               "xor %2, %2                \n"
-                               "0:                        \n"
-                               "movups (%4,%2),%%xmm1     \n"
-                               "movups (%3,%2),%%xmm2     \n"
-                               "mulps %%xmm2,%%xmm1       \n"
-                               "addps %%xmm1,%1           \n"
-                               "add $16,%2                \n"
-                               "dec %5                    \n"
-                               "jnz 0b                    \n"
-                               "haddps %1,%1              \n"
-                               "haddps %1,%1              \n"
-                               "maxss %6,%1               \n"
-                               "minss %7,%1               \n"
-                               "cvtss2si %1,%0            \n"
-                               : "=r" (result),
-                                 "=&x" (acc),
-                                 "=&r" (tmp)
-                               : "r" (&coeffs[pd[x].startcoeff]),
-                                 "r" (&sptr[pd[x].start]),
-                                 "r" ((pd[x].end - pd[x].start + 1)/4),
-                                 "m" (low),
-                                 "m" (high)
-                               : "memory", "xmm1", "xmm2"
-                       );
-
-#if 0
-                       if (acc < 0.0)
-                               ch = 0;
-                       else if (acc > 255.0)
-                               ch = 255;
-                       else
-                               ch = (unsigned char)acc;
-                       *dptr++ = ch;
-#endif
-                       *dptr++ = (unsigned char)result;
-               }
-               ch = dptr[-1];
-               for ( ; x < dstride; ++x) {
-                       *dptr++ = ch;
-               }
-       }
-}
-
-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;
-       float *coeffs = (float *)malloc(size_coeffs * sizeof(float));
-       int num_coeffs = 0;
-       int x, y, sy;
-       double sf = (double)h / (double)nh;
-       double support = (h > nh) ? (3.0 * sf) : (3.0 / sf);
-
-       /* calculate the filter */
-       for (y = 0; y < nh; ++y) {
-               int start = ceil(y * sf - support);
-               int end = floor(y * sf + support);
-               double sum = 0.0;
-
-               if (start < 0) {
-                       start = 0;
-               }
-               if (end > h - 1) {
-                       end = h - 1;
-               }
-
-               pd[y].start = start;
-               pd[y].end = end;
-               pd[y].startcoeff = num_coeffs;
-
-               for (sy = start; sy <= end; ++sy) {
-                       double nd = (h > nh) ? (sy/sf - y) : (sy - y*sf);
-                       double f = lanczos_tap(nd);
-                       if (num_coeffs == size_coeffs) {
-                               size_coeffs <<= 1;
-                               coeffs = (float *)realloc(coeffs, size_coeffs * sizeof(float));
-                       }
-                       
-                       coeffs[num_coeffs++] = f;
-                       sum += f;
-               }
-
-               for (sy = start; sy <= end; ++sy) {
-                       coeffs[pd[y].startcoeff + sy - start] /= sum;
-               }
-       }
-
-#if CACHE_LINE_FACTOR > 1
-       for (x = 0; x < (w/CACHE_LINE_FACTOR) * CACHE_LINE_FACTOR; x += CACHE_LINE_FACTOR) {
-               unsigned char *sptr = pix + x;
-               float *dptr = npix + x;
-               for (y = 0; y < nh; ++y) {
-#if 0
-                       int i;
-                       float acc[CACHE_LINE_FACTOR];
-                       for (i = 0; i < CACHE_LINE_FACTOR; ++i)
-                               acc[i] = 0.0;
-                       float *cf = &coeffs[pd[y].startcoeff];
-                       unsigned sy;
-               
-                       for (sy = pd[y].start; sy <= pd[y].end; ++sy) {
-                               for (i = 0; i < CACHE_LINE_FACTOR; ++i) {
-                                       acc[i] += sptr[sy * w + i] * *cf;
-                               }
-                               ++cf;
-                       }
-
-                       for (i = 0; i < CACHE_LINE_FACTOR; ++i) {
-                               dptr[i] = acc[i];
-                       }
-#else
-                       /*
-                        * xmm0 - xmm3: acc[0..15]
-                        * xmm4: current filter coefficient
-                        * xmm5, xmm6, xmm7: scratchpad
-                        */
-                       __asm__ (
-                               /* clear */
-                               "pxor %%xmm0, %%xmm0          \n"
-                               "pxor %%xmm1, %%xmm1          \n"
-                               "pxor %%xmm2, %%xmm2          \n"
-                               "pxor %%xmm3, %%xmm3          \n"
-
-                               /* main loop */
-                               "0:                           \n"
-                               
-                               /* a zero is useful during unpacking */
-                               "pxor %%xmm4, %%xmm4          \n"
-                               
-                               /* fetch all 16 source bytes */
-                               "movups (%0), %%xmm5          \n"
-                               "prefetcht0 (%0,%3,4)         \n"
-
-                               /* unpack into words (xmm5, xmm7) */
-                               "movaps %%xmm5, %%xmm7        \n"
-                               "punpcklbw %%xmm4, %%xmm5     \n"
-                               "punpckhbw %%xmm4, %%xmm7     \n"
-
-                               /* unpack xmm5 into dwords (xmm5, xmm6) */
-                               "movaps %%xmm5, %%xmm6        \n"
-                               "punpcklwd %%xmm4, %%xmm5     \n"
-                               "punpckhwd %%xmm4, %%xmm6     \n"
-
-                               /* convert xmm5, xmm6 to floats */
-                               "cvtdq2ps %%xmm5, %%xmm5      \n"
-                               "cvtdq2ps %%xmm6, %%xmm6      \n"
-
-                               /* fetch the coefficient */
-                               "movss (%2), %%xmm4           \n"
-                               "shufps $0x0, %%xmm4, %%xmm4  \n"
-
-                               /* do the muls for xmm5 and xmm6 */
-                               "mulps %%xmm4, %%xmm5         \n"
-                               "mulps %%xmm4, %%xmm6         \n"
-                               "addps %%xmm5, %%xmm0         \n"
-                               "addps %%xmm6, %%xmm1         \n"
-
-                               /* get the zero back again */
-                               "pxor %%xmm4, %%xmm4          \n"
-
-                               /* unpack xmm7 into dwords (xmm7, xmm6) */
-                               "movaps %%xmm7, %%xmm6        \n"
-                               "punpcklwd %%xmm4, %%xmm7     \n"
-                               "punpckhwd %%xmm4, %%xmm6     \n"
-
-                               /* convert xmm7, xmm6 to floats */
-                               "cvtdq2ps %%xmm7, %%xmm7      \n"
-                               "cvtdq2ps %%xmm6, %%xmm6      \n"
-
-                               /* fetch the coefficient */
-                               "movss (%2), %%xmm4           \n"
-                               "shufps $0x0, %%xmm4, %%xmm4  \n"
-
-                               /* do the second set of muls */
-                               "mulps %%xmm4, %%xmm7         \n"
-                               "mulps %%xmm4, %%xmm6         \n"
-                               "addps %%xmm7, %%xmm2         \n"
-                               "addps %%xmm6, %%xmm3         \n"
-
-                               /* move along, and loop */
-                               "add $4, %2                   \n"
-                               "add %3, %0                   \n"
-                               "dec %1                       \n"
-                               "jnz 0b                       \n"
-
-                               /* store the values */
-                               "movaps %%xmm0, (%4)          \n"
-                               "movaps %%xmm1, 16(%4)        \n"
-                               "movaps %%xmm2, 32(%4)        \n"
-                               "movaps %%xmm3, 48(%4)        \n"
-                               : :
-                               "r" (&sptr[pd[y].start * w]),        /* 0: srcptr base */
-                               "r" (pd[y].end - pd[y].start + 1),   /* 1: filter len */
-                               "r" (&coeffs[pd[y].startcoeff]),     /* 2: coeffs base */
-                               "r" ((long)w),                       /* 3: stride */
-                               "r" (dptr)                           /* 4: dstptr base */
-                               : "memory", "xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5", "xmm6", "xmm7"
-                       );
-#endif
-                       dptr += dstride;
-               }
-       }
-       for (x = (x/CACHE_LINE_FACTOR)*CACHE_LINE_FACTOR; x < w; ++x) {
-#else
-       for (x = 0; x < w; ++x) {
-#endif
-               unsigned char *sptr = pix + x;
-               float *dptr = npix + x;
-               for (y = 0; y < nh; ++y) {
-                       float acc = 0.0;
-                       float *cf = &coeffs[pd[y].startcoeff];
-                       unsigned sy;
-                       
-                       for (sy = pd[y].start; sy <= pd[y].end; ++sy) {
-                               acc += sptr[sy * w] * *cf++;
-                       }
-
-                       *dptr = acc;
-                       dptr += dstride;
-               }
-       }
-}
+#include "libqscale.h"
 
 int main(int argc, char **argv)
 {
+       /* user-settable parameters */
        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);
-
-       unsigned w0 = dinfo.image_width * dinfo.comp_info[0].h_samp_factor / dinfo.max_h_samp_factor;
-       unsigned h0 = dinfo.image_height * dinfo.comp_info[0].v_samp_factor / dinfo.max_v_samp_factor;
-
-       unsigned w1 = dinfo.image_width * dinfo.comp_info[1].h_samp_factor / dinfo.max_h_samp_factor;
-       unsigned h1 = dinfo.image_height * dinfo.comp_info[1].v_samp_factor / dinfo.max_v_samp_factor;
-
-       unsigned w2 = dinfo.image_width * dinfo.comp_info[2].h_samp_factor / dinfo.max_h_samp_factor;
-       unsigned h2 = dinfo.image_height * dinfo.comp_info[2].v_samp_factor / dinfo.max_v_samp_factor;
-
-       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*)memalign(16, dinfo.comp_info[0].height_in_blocks * dinfo.comp_info[0].width_in_blocks * DCTSIZE * DCTSIZE);
-       JSAMPLE *data_cb = (JSAMPLE*)memalign(16, dinfo.comp_info[1].height_in_blocks * dinfo.comp_info[1].width_in_blocks * DCTSIZE * DCTSIZE);
-       JSAMPLE *data_cr = (JSAMPLE*)memalign(16, 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 (jpeg_read_raw_data(&dinfo, ptrs, max_lines) == 0)
-                       break;
-       }
-
-       {
-               float *npix = (float*)memalign(16, dinfo.comp_info[0].width_in_blocks * DCTSIZE * nh0 * sizeof(float)); 
-               vscale(data_y, npix, dinfo.comp_info[0].width_in_blocks * DCTSIZE, h0, nh0, dinfo.comp_info[0].width_in_blocks * DCTSIZE);
-               data_ny = (unsigned char *)malloc(nw0 * stride0);
-               hscale(npix, data_ny, w0, nh0, nw0, dinfo.comp_info[0].width_in_blocks * DCTSIZE, stride0);
-               free(npix);
-       }
-       {
-               float *npix = (float*)memalign(16, dinfo.comp_info[1].width_in_blocks * DCTSIZE * nh1 * sizeof(float)); 
-               vscale(data_cr, npix, dinfo.comp_info[1].width_in_blocks * DCTSIZE, h1, nh1, dinfo.comp_info[1].width_in_blocks * DCTSIZE);
-               data_ncr = (unsigned char *)malloc(nw1 * stride1);
-               hscale(npix, data_ncr, w1, nh1, nw1, dinfo.comp_info[1].width_in_blocks * DCTSIZE, stride1);
-               free(npix);
-       }
-       {
-               float *npix = (float*)memalign(16, dinfo.comp_info[2].width_in_blocks * DCTSIZE * nh2 * sizeof(float)); 
-               vscale(data_cb, npix, dinfo.comp_info[2].width_in_blocks * DCTSIZE, h2, nh2, dinfo.comp_info[2].width_in_blocks * DCTSIZE);
-               data_ncb = (unsigned char *)malloc(nw2 * stride2);
-               hscale(npix, data_ncb, w2, nh2, nw2, dinfo.comp_info[2].width_in_blocks * DCTSIZE, stride2);
-               free(npix);
-       }
-       jpeg_destroy_decompress(&dinfo);
-       
-       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;
+       unsigned jpeg_quality = 85;
+       /* end */
 
-               jpeg_write_raw_data(&cinfo, ptrs, max_lines);
-       }
-       jpeg_finish_compress(&cinfo);
-       jpeg_destroy_compress(&cinfo);
+       qscale_img *img = qscale_load_jpeg_from_stdio(stdin);
+       qscale_img *scaled = qscale_scale(img, nominal_w, nominal_h, samp_h0, samp_v0, samp_h1, samp_v1, samp_h2, samp_v2, LANCZOS);
+       qscale_destroy(img);
+       qscale_save_jpeg_to_stdio(scaled, stdout, jpeg_quality, SEQUENTIAL);
 
        return 0;
 }