Changeset 3521Tweet

Timestamp:

May 25, 2009, 2:16:50 AM (11 years ago)

Author:

Sam Hocevar

Message:

Add proper Unicode handling to img2twit. This includes an UTF-8 encoder/decoder
and a special bit stack that can handle arbitrary bases within its stream. The
image encoder and decoder are now separate code paths.

File:

• libpipi/trunk/examples/img2twit.cpp (modified) (7 diffs)

libpipi/trunk/examples/img2twit.cpp

@@ -16 +16 @@
  */
 
+/* Debug mode */
+#define DEBUG 1
+
+/* Encoding iterations: 1000 gives a fast answer, 10000 gives good quality */
+#define MAX_ITERATIONS 10000
+
 /* The maximum message length */
 #define MAX_MSG_LEN 140
 
-/* The number of characters at disposal */
-//#define NUM_CHARACTERS 0x7fffffff // The sky's the limit
-//#define NUM_CHARACTERS 1111998 // Full valid Unicode set
-//#define NUM_CHARACTERS 100507 // Full graphic Unicode
-#define NUM_CHARACTERS 32768 // Chinese characters
-//#define NUM_CHARACTERS 127 // ASCII
+/* The Unicode characters at disposal - XXX: must be _ordered_ */
+static const uint32_t unichars[] =
+{
+    /* Printable ASCII (except space) */
+    0x0021, 0x007f,
+
+    /* Stupid symbols and Dingbats shit */
+    //0x25a0, 0x2600, /* Geometric Shapes */
+    //0x2600, 0x269e, 0x26a0, 0x26bd, 0x26c0, 0x26c4, /* Misc. Symbols */
+    //0x2701, 0x2705, 0x2706, 0x270a, 0x270c, 0x2728, 0x2729, 0x274c,
+    //  0x274d, 0x274e, 0x274f, 0x2753, 0x2756, 0x2757, 0x2758, 0x275f,
+    //  0x2761, 0x2795, 0x2798, 0x27b0, 0x27b1, 0x27bf, /* Dingbats */
+
+    /* Chinese-looking stuff */
+    //0x2e80, 0x2e9a, 0x2e9b, 0x2ef4, /* CJK Radicals Supplement */
+    //0x2f00, 0x2fd6, /* Kangxi Radicals */
+    //0x3400, 0x4db6, /* CJK Unified Ideographs Extension A */
+    //0x4e00, 0x9fa6, /* CJK Unified Ideographs */
+
+    /* Korean - most people don't know the difference anyway */
+    0xac00, 0xd7a4, /* Hangul Syllables */
+
+    /* More Chinese */
+    //0xf900, 0xfa2e, 0xfa30, 0xfa6b, 0xfa70, 0xfada, /* CJK Compat. Idgphs. */
+
+    /* TODO: there's also the U+20000 and U+2f800 planes, but they're
+     * not supported by the Twitter Javascript filter (yet?). */
+
+    /* End of list marker - XXX: don't remove! */
+    0x0000, 0x0000
+};
 
 /* The maximum image size we want to support */
@@ -54 +85 @@
 static float HEADER_BITS;
 static float DATA_BITS;
-static float POINT_BITS;
-
+static float CELL_BITS;
+
+static int NUM_CHARACTERS;
 static unsigned int TOTAL_CELLS;
 
@@ -78 +110 @@
 static Delaunay_triangulation dt;
 
+/*
+ * Unicode stuff handling
+ */
+
+/* Return the number of chars in the unichars table */
+static int count_unichars(void)
+{
+    int ret = 0;
+
+    for(int u = 0; unichars[u] != unichars[u + 1]; u += 2)
+        ret += unichars[u + 1] - unichars[u];
+
+    return ret;
+}
+
+/* Get the ith Unicode character in our list */
+static uint32_t index2uni(uint32_t i)
+{
+    for(int u = 0; unichars[u] != unichars[u + 1]; u += 2)
+        if(i < unichars[u + 1] - unichars[u])
+            return unichars[u] + i;
+        else
+            i -= unichars[u + 1] - unichars[u];
+
+    return 0; /* Should not happen! */
+}
+
+/* Convert a Unicode character to its position in the compact list */
+static uint32_t uni2index(uint32_t x)
+{
+    uint32_t ret = 0;
+
+    for(int u = 0; unichars[u] != unichars[u + 1]; u += 2)
+        if(x < unichars[u + 1])
+            return ret + x - unichars[u];
+        else
+            ret += unichars[u + 1] - unichars[u];
+
+    return ret; /* Should not happen! */
+}
+
+static uint8_t const utf8_trailing[256] =
+{
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5
+};
+
+static uint32_t const utf8_offsets[6] =
+{
+    0x00000000UL, 0x00003080UL, 0x000E2080UL,
+    0x03C82080UL, 0xFA082080UL, 0x82082080UL
+};
+
+static uint32_t fread_utf8(FILE *f)
+{
+    int ch, i = 0, todo = -1;
+    uint32_t ret = 0;
+
+    for(;;)
+    {
+        ch = fgetc(f);
+        if(!ch)
+            return 0;
+        if(todo == -1)
+            todo = utf8_trailing[ch];
+        ret += ((uint32_t)ch) << (6 * (todo - i));
+        if(todo == i++)
+            return ret - utf8_offsets[todo];
+    }
+}
+
+static void fwrite_utf8(FILE *f, uint32_t x)
+{
+    static const uint8_t mark[7] =
+    {
+        0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC
+    };
+
+    char buf[8];
+    char *parser = buf;
+    size_t bytes;
+
+    if(x < 0x80)
+    {
+        fprintf(f, "%c", x);
+        return;
+    }
+
+    bytes = (x < 0x800) ? 2 : (x < 0x10000) ? 3 : 4;
+    parser += bytes;
+    *parser = '\0';
+
+    switch(bytes)
+    {
+        case 4: *--parser = (x | 0x80) & 0xbf; x >>= 6;
+        case 3: *--parser = (x | 0x80) & 0xbf; x >>= 6;
+        case 2: *--parser = (x | 0x80) & 0xbf; x >>= 6;
+    }
+    *--parser = x | mark[bytes];
+
+    fprintf(f, "%s", buf);
+}
+
+/*
+ * Our nifty non-power-of-two bitstack handling
+ */
+
+class bitstack
+{
+public:
+    bitstack() { init(0); }
+
+    char const *tostring()
+    {
+        int pos = sprintf(str, "0x%x", digits[msb]);
+
+        for(int i = msb - 1; i >= 0; i--)
+            pos += sprintf(str + pos, "%08x", digits[i]);
+
+        return str;
+    }
+
+    void push(uint32_t val, uint32_t range)
+    {
+        if(!range)
+            return;
+
+        mul(range);
+        add(val % range);
+    }
+
+    uint32_t pop(uint32_t range)
+    {
+        if(!range)
+            return 0;
+
+        return div(range);
+    }
+
+    bool isempty()
+    {
+        for(int i = msb; i >= 0; i--)
+            if(digits[i])
+                return false;
+
+        return true;
+    }
+
+private:
+    bitstack(uint32_t i) { init(i); }
+
+    void init(uint32_t i)
+    {
+        memset(digits, 0, sizeof(digits));
+        digits[0] = i;
+        msb = 0;
+    }
+
+    /* Could be done much faster, but we don't care! */
+    void add(uint32_t x) { add(bitstack(x)); }
+    void sub(uint32_t x) { sub(bitstack(x)); }
+
+    void add(bitstack const &_b)
+    {
+        /* Copy the operand in case we get added to ourselves */
+        bitstack b = _b;
+        uint64_t x = 0;
+
+        if(msb < b.msb)
+            msb = b.msb;
+
+        for(int i = 0; i <= msb; i++)
+        {
+            uint64_t tmp = (uint64_t)digits[i] + (uint64_t)b.digits[i] + x;
+            digits[i] = tmp;
+            if((uint64_t)digits[i] == tmp)
+                x = 0;
+            else
+            {
+                x = 1;
+                if(i == msb)
+                    msb++;
+            }
+        }
+    }
+
+    void sub(bitstack const &_b)
+    {
+        /* Copy the operand in case we get substracted from ourselves */
+        bitstack b = _b;
+        uint64_t x = 0;
+
+        /* We cannot substract a larger number! */
+        if(msb < b.msb)
+        {
+            init(0);
+            return;
+        }
+
+        for(int i = 0; i <= msb; i++)
+        {
+            uint64_t tmp = (uint64_t)digits[i] - (uint64_t)b.digits[i] - x;
+            digits[i] = tmp;
+            if((uint64_t)digits[i] == tmp)
+                x = 0;
+            else
+            {
+                x = 1;
+                if(i == msb)
+                {
+                    /* Error: carry into MSB! */
+                    init(0);
+                    return;
+                }
+            }
+        }
+
+        while(msb > 0 && digits[msb] == 0) msb--;
+    }
+
+    void mul(uint32_t x)
+    {
+        bitstack b = *this;
+        init(0);
+
+        while(x)
+        {
+            if(x & 1)
+                add(b);
+            x /= 2;
+            b.add(b);
+        }
+    }
+
+    uint32_t div(uint32_t x)
+    {
+        bitstack b = *this;
+
+        for(int i = msb; i >= 0; i--)
+        {
+            uint64_t tmp = b.digits[i] + (((uint64_t)b.digits[i + 1]) << 32);
+            uint32_t res = tmp / x;
+            uint32_t rem = tmp % x;
+            digits[i]= res;
+            b.digits[i + 1] = 0;
+            b.digits[i] = rem;
+        }
+
+        while(msb > 0 && digits[msb] == 0) msb--;
+
+        return b.digits[0];
+    }
+
+    int msb;
+    uint32_t digits[MAX_MSG_LEN + 1]; /* This is a safe max value */
+    char str[(MAX_MSG_LEN + 1) * 8 + 1];
+};
+
+/*
+ * Point handling
+ */
+
 static unsigned int det_rand(unsigned int mod)
 {
@@ -157 +457 @@
 }
 
+#if 0
 static void add_random_point()
 {
@@ -162 +463 @@
     npoints++;
 }
+#endif
 
 #define NB_OPS 20
@@ -439 +741 @@
 {
     int opstats[2 * NB_OPS];
+    bitstack b;
     pipi_image_t *src, *tmp, *dst;
     double error = 1.0;
     int width, height, ret = 0;
-
-    /* Compute bit allocation */
-    fprintf(stderr, "Available characters: %i\n", NUM_CHARACTERS);
-    fprintf(stderr, "Maximum message size: %i\n", MAX_MSG_LEN);
+    bool decode = (argc >= 2 && !strcmp(argv[1], "-o"));
+
+    if(!((argc == 2 && !decode) || (argc == 3 && decode)))
+    {
+        fprintf(stderr, "img2twit: wrong argument count\n");
+        fprintf(stderr, "Usage: img2twit <image>        Encode image and print result to stdout\n");
+        fprintf(stderr, "       img2twit -o <image>     Read data from stdin and decode image to file\n");
+        return EXIT_FAILURE;
+    }
+
+    pipi_set_gamma(1.0);
+
+    /* Precompute bit allocation */
+    NUM_CHARACTERS = count_unichars();
     TOTAL_BITS = MAX_MSG_LEN * logf(NUM_CHARACTERS) / logf(2);
-    fprintf(stderr, "Available bits: %f\n", TOTAL_BITS);
-    fprintf(stderr, "Maximum image resolution: %ix%i\n", MAX_W, MAX_H);
     HEADER_BITS = logf(MAX_W * MAX_H) / logf(2);
-    fprintf(stderr, "Header bits: %f\n", HEADER_BITS);
     DATA_BITS = TOTAL_BITS - HEADER_BITS;
-    fprintf(stderr, "Bits available for data: %f\n", DATA_BITS);
 #if POINTS_PER_CELL == 1
-    POINT_BITS = logf(RANGE_SYXRGB) / logf(2);
+    CELL_BITS = logf(RANGE_SYXRGB) / logf(2);
 #else
-    float coord_bits = logf((RANGE_Y * RANGE_X) * (RANGE_Y * RANGE_X + 1) / 2);
-    float other_bits = logf(RANGE_R * RANGE_G * RANGE_B * RANGE_S);
-    POINT_BITS = (coord_bits + 2 * other_bits) / logf(2);
-#endif
-    fprintf(stderr, "Cell bits: %f\n", POINT_BITS);
-    TOTAL_CELLS = (int)(DATA_BITS / POINT_BITS);
-    fprintf(stderr, "Available cells: %i\n", TOTAL_CELLS);
-    fprintf(stderr, "Wasted bits: %f\n", DATA_BITS - POINT_BITS * TOTAL_CELLS);
-
-    /* Load image */
-    pipi_set_gamma(1.0);
-    src = pipi_load(argv[1]);
-    width = pipi_get_image_width(src);
-    height = pipi_get_image_height(src);
+    // TODO: implement the following shit
+    //float coord_bits = logf((RANGE_Y * RANGE_X) * (RANGE_Y * RANGE_X + 1) / 2);
+    //float other_bits = logf(RANGE_R * RANGE_G * RANGE_B * RANGE_S);
+    //CELL_BITS = (coord_bits + 2 * other_bits) / logf(2);
+    CELL_BITS = 2 * logf(RANGE_SYXRGB) / logf(2);
+#endif
+    TOTAL_CELLS = (int)(DATA_BITS / CELL_BITS);
+
+    if(decode)
+    {
+        /* Decoding mode: read UTF-8 text from stdin, find each
+         * character's index in our character list, and push it to our
+         * wonderful custom bitstream. */
+        uint32_t data[MAX_MSG_LEN];
+        for(int i = 0; i < MAX_MSG_LEN; i++)
+            data[i] = uni2index(fread_utf8(stdin));
+        for(int i = MAX_MSG_LEN; i--; )
+            b.push(data[i], NUM_CHARACTERS);
+
+        /* Read width and height from bitstream */
+        src = NULL;
+        width = b.pop(MAX_W);
+        height = b.pop(MAX_H);
+    }
+    else
+    {
+        /* Argument given: open image for encoding */
+        src = pipi_load(argv[1]);
+
+        if(!src)
+        {
+            fprintf(stderr, "Error loading %s\n", argv[1]);
+            return EXIT_FAILURE;
+        }
+
+        width = pipi_get_image_width(src);
+        height = pipi_get_image_height(src);
+    }
 
     /* Compute best w/h ratio */
@@ -489 +822 @@
     while((dh + 1) * dw <= TOTAL_CELLS) dh++;
     while(dw * (dh + 1) <= TOTAL_CELLS) dw++;
+
+    /* Print debug information */
+#if DEBUG
+    fprintf(stderr, "Maximum message size: %i\n", MAX_MSG_LEN);
+    fprintf(stderr, "Available characters: %i\n", NUM_CHARACTERS);
+    fprintf(stderr, "Available bits: %f\n", TOTAL_BITS);
+    fprintf(stderr, "Maximum image resolution: %ix%i\n", MAX_W, MAX_H);
+    fprintf(stderr, "Image resolution: %ix%i\n", width, height);
+    fprintf(stderr, "Header bits: %f\n", HEADER_BITS);
+    fprintf(stderr, "Bits available for data: %f\n", DATA_BITS);
+    fprintf(stderr, "Cell bits: %f\n", CELL_BITS);
+    fprintf(stderr, "Available cells: %i\n", TOTAL_CELLS);
+    fprintf(stderr, "Wasted bits: %f\n", DATA_BITS - CELL_BITS * TOTAL_CELLS);
+
     fprintf(stderr, "Chosen image ratio: %i:%i (wasting %i point cells)\n",
             dw, dh, TOTAL_CELLS - dw * dh);
     fprintf(stderr, "Total wasted bits: %f\n",
-            DATA_BITS - POINT_BITS * dw * dh);
-
-    /* Resize and filter image to better state */
-    tmp = pipi_resize(src, dw * RANGE_X, dh * RANGE_Y);
-    pipi_free(src);
-    src = pipi_median_ext(tmp, 1, 1);
-    pipi_free(tmp);
-
-    /* Analyse image */
-    analyse(src);
-
-    /* Render what we just computed */
-    tmp = pipi_new(dw * RANGE_X, dh * RANGE_Y);
-    render(tmp, 0, 0, dw * RANGE_X, dh * RANGE_Y);
-    error = pipi_measure_rmsd(src, tmp);
-
-    fprintf(stderr, "Distance: %2.10g\n", error);
-
-    memset(opstats, 0, sizeof(opstats));
-    for(int iter = 0, stuck = 0, failures = 0, success = 0;
-        /*stuck < 5 && */iter < 10000;
-        iter++)
-    {
-        if(failures > 500)
-        {
-            stuck++;
-            failures = 0;
-        }
-
-        pipi_image_t *scrap = pipi_copy(tmp);
-
-        /* Choose a point at random */
-        int pt = det_rand(npoints);
-        uint32_t oldval = points[pt];
-
-        /* Compute the affected image zone */
-        float fx, fy, fr, fg, fb, fs;
-        get_point(pt, &fx, &fy, &fr, &fg, &fb, &fs);
-        int zonex = (int)fx / RANGE_X - 1;
-        int zoney = (int)fy / RANGE_Y - 1;
-        int zonew = 3;
-        int zoneh = 3;
-        if(zonex < 0) { zonex = 0; zonew--; }
-        if(zoney < 0) { zoney = 0; zoneh--; }
-        if(zonex + zonew >= (int)dw) { zonew--; }
-        if(zoney + zoneh >= (int)dh) { zoneh--; }
-
-        /* Choose random operations and measure their effect */
-        uint8_t op1 = rand_op();
-        //uint8_t op2 = rand_op();
-
-        uint32_t candidates[3];
-        double besterr = error + 1.0;
-        int bestop = -1;
-        candidates[0] = apply_op(op1, oldval);
-        //candidates[1] = apply_op(op2, oldval);
-        //candidates[2] = apply_op(op1, apply_op(op2, oldval));
-
-        for(int i = 0; i < 1; i++)
-        //for(int i = 0; i < 3; i++)
-        {
-            if(oldval == candidates[i])
-                continue;
-
-            points[pt] = candidates[i];
-
-            render(scrap, zonex * RANGE_X, zoney * RANGE_Y,
-                   zonew * RANGE_X, zoneh * RANGE_Y);
-
-            double newerr = pipi_measure_rmsd(src, scrap);
-            if(newerr < besterr)
+            DATA_BITS - CELL_BITS * dw * dh);
+#endif
+
+    if(src)
+    {
+        /* Resize and filter image to better state */
+        tmp = pipi_resize(src, dw * RANGE_X, dh * RANGE_Y);
+        pipi_free(src);
+        src = pipi_median_ext(tmp, 1, 1);
+        pipi_free(tmp);
+
+        /* Analyse image */
+        analyse(src);
+
+        /* Render what we just computed */
+        tmp = pipi_new(dw * RANGE_X, dh * RANGE_Y);
+        render(tmp, 0, 0, dw * RANGE_X, dh * RANGE_Y);
+        error = pipi_measure_rmsd(src, tmp);
+
+#if DEBUG
+        fprintf(stderr, "Distance: %2.10g\n", error);
+#endif
+
+        memset(opstats, 0, sizeof(opstats));
+        for(int iter = 0, stuck = 0, failures = 0, success = 0;
+            iter < MAX_ITERATIONS /* && stuck < 5 && */;
+            iter++)
+        {
+            if(failures > 500)
             {
-                besterr = newerr;
-                bestop = i;
+                stuck++;
+                failures = 0;
             }
-        }
-
-        opstats[op1 * 2]++;
-        //opstats[op2 * 2]++;
-
-        if(besterr < error)
-        {
-            points[pt] = candidates[bestop];
-            /* Redraw image if the last check wasn't the best one */
-            if(bestop != 2)
+
+#if !DEBUG
+            if(!(iter % 16))
+                fprintf(stderr, "\rEncoding... %i%%",
+                        iter * 100 / MAX_ITERATIONS);
+#endif
+
+            pipi_image_t *scrap = pipi_copy(tmp);
+
+            /* Choose a point at random */
+            int pt = det_rand(npoints);
+            uint32_t oldval = points[pt];
+
+            /* Compute the affected image zone */
+            float fx, fy, fr, fg, fb, fs;
+            get_point(pt, &fx, &fy, &fr, &fg, &fb, &fs);
+            int zonex = (int)fx / RANGE_X - 1;
+            int zoney = (int)fy / RANGE_Y - 1;
+            int zonew = 3;
+            int zoneh = 3;
+            if(zonex < 0) { zonex = 0; zonew--; }
+            if(zoney < 0) { zoney = 0; zoneh--; }
+            if(zonex + zonew >= (int)dw) { zonew--; }
+            if(zoney + zoneh >= (int)dh) { zoneh--; }
+
+            /* Choose random operations and measure their effect */
+            uint8_t op1 = rand_op();
+            //uint8_t op2 = rand_op();
+
+            uint32_t candidates[3];
+            double besterr = error + 1.0;
+            int bestop = -1;
+            candidates[0] = apply_op(op1, oldval);
+            //candidates[1] = apply_op(op2, oldval);
+            //candidates[2] = apply_op(op1, apply_op(op2, oldval));
+
+            for(int i = 0; i < 1; i++)
+            //for(int i = 0; i < 3; i++)
+            {
+                if(oldval == candidates[i])
+                    continue;
+
+                points[pt] = candidates[i];
+
                 render(scrap, zonex * RANGE_X, zoney * RANGE_Y,
                        zonew * RANGE_X, zoneh * RANGE_Y);
 
-            pipi_free(tmp);
-            tmp = scrap;
-            //fprintf(stderr, "%08i %2.010g %2.010g after op%i(%i)\n",
-            //        iter, besterr - error, error, op1, pt);
-            fprintf(stderr, "%08i -.%08i %2.010g after op%i(%i)\n", iter,
-                    (int)((error - besterr) * 100000000), error, op1, pt);
-            error = besterr;
-            opstats[op1 * 2 + 1]++;
-            //opstats[op2 * 2 + 1]++;
-            failures = 0;
-            success++;
-
-            /* Save image! */
-            //char buf[128];
-            //sprintf(buf, "twit%08i.bmp", success);
-            //if((success % 10) == 0)
-            //    pipi_save(tmp, buf);
-        }
-        else
-        {
-            pipi_free(scrap);
-            points[pt] = oldval;
-            failures++;
-        }
-    }
-
-    for(int j = 0; j < 2; j++)
-    {
-        fprintf(stderr,   "operation: ");
-        for(int i = NB_OPS / 2 * j; i < NB_OPS / 2 * (j + 1); i++)
-            fprintf(stderr, "%4i ", i);
-        fprintf(stderr, "\nattempts:  ");
-        for(int i = NB_OPS / 2 * j; i < NB_OPS / 2 * (j + 1); i++)
-            fprintf(stderr, "%4i ", opstats[i * 2]);
-        fprintf(stderr, "\nsuccesses: ");
-        for(int i = NB_OPS / 2 * j; i < NB_OPS / 2 * (j + 1); i++)
-            fprintf(stderr, "%4i ", opstats[i * 2 + 1]);
-        fprintf(stderr, "\n");
-    }
-
-    fprintf(stderr, "Distance: %2.10g\n", error);
-
-    dst = pipi_resize(tmp, width, height);
-    pipi_free(tmp);
-
-    /* Save image and bail out */
-    pipi_save(dst, "lol.bmp");
-    pipi_free(dst);
+                double newerr = pipi_measure_rmsd(src, scrap);
+                if(newerr < besterr)
+                {
+                    besterr = newerr;
+                    bestop = i;
+                }
+            }
+
+            opstats[op1 * 2]++;
+            //opstats[op2 * 2]++;
+
+            if(besterr < error)
+            {
+                points[pt] = candidates[bestop];
+                /* Redraw image if the last check wasn't the best one */
+                if(bestop != 2)
+                    render(scrap, zonex * RANGE_X, zoney * RANGE_Y,
+                           zonew * RANGE_X, zoneh * RANGE_Y);
+
+                pipi_free(tmp);
+                tmp = scrap;
+#if DEBUG
+                fprintf(stderr, "%08i -.%08i %2.010g after op%i(%i)\n", iter,
+                        (int)((error - besterr) * 100000000), error, op1, pt);
+#endif
+                error = besterr;
+                opstats[op1 * 2 + 1]++;
+                //opstats[op2 * 2 + 1]++;
+                failures = 0;
+                success++;
+
+                /* Save image! */
+                //char buf[128];
+                //sprintf(buf, "twit%08i.bmp", success);
+                //if((success % 10) == 0)
+                //    pipi_save(tmp, buf);
+            }
+            else
+            {
+                pipi_free(scrap);
+                points[pt] = oldval;
+                failures++;
+            }
+        }
+
+        fprintf(stderr, "\r                    \r");
+
+#if DEBUG
+        for(int j = 0; j < 2; j++)
+        {
+            fprintf(stderr,   "operation: ");
+            for(int i = NB_OPS / 2 * j; i < NB_OPS / 2 * (j + 1); i++)
+                fprintf(stderr, "%4i ", i);
+            fprintf(stderr, "\nattempts:  ");
+            for(int i = NB_OPS / 2 * j; i < NB_OPS / 2 * (j + 1); i++)
+                fprintf(stderr, "%4i ", opstats[i * 2]);
+            fprintf(stderr, "\nsuccesses: ");
+            for(int i = NB_OPS / 2 * j; i < NB_OPS / 2 * (j + 1); i++)
+                fprintf(stderr, "%4i ", opstats[i * 2 + 1]);
+            fprintf(stderr, "\n");
+        }
+
+        fprintf(stderr, "Distance: %2.10g\n", error);
+#endif
+
+#if 0
+        dst = pipi_resize(tmp, width, height);
+        pipi_free(tmp);
+
+        /* Save image and bail out */
+        pipi_save(dst, "lol.bmp");
+        pipi_free(dst);
+#endif
+
+        /* Push our points to the bitstream */
+        for(int i = 0; i < npoints; i++)
+            b.push(points[i], RANGE_SYXRGB);
+        b.push(height, MAX_H);
+        b.push(width, MAX_W);
+
+        /* Pop Unicode characters from the bitstream and print them */
+        for(int i = 0; i < MAX_MSG_LEN; i++)
+            fwrite_utf8(stdout, index2uni(b.pop(NUM_CHARACTERS)));
+        fprintf(stdout, "\n");
+    }
+    else
+    {
+        /* Pop points from the bitstream */
+        for(int i = dw * dh; i--; )
+        {
+#if POINTS_PER_CELL == 2
+            points[i * 2 + 1] = b.pop(RANGE_SYXRGB);
+            points[i * 2] = b.pop(RANGE_SYXRGB);
+#else
+            points[i] = b.pop(RANGE_SYXRGB);
+#endif
+        }
+        npoints = dw * dh * POINTS_PER_CELL;
+
+        /* Render these points to a new image */
+        tmp = pipi_new(dw * RANGE_X, dh * RANGE_Y);
+        render(tmp, 0, 0, dw * RANGE_X, dh * RANGE_Y);
+
+        /* TODO: render directly to the final image; scaling sucks */
+        dst = pipi_resize(tmp, width, height);
+        pipi_free(tmp);
+
+        /* Save image and bail out */
+        pipi_save(dst, argv[2]);
+        pipi_free(dst);
+    }
 
     return ret;