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-rw-r--r--sixel.c690
1 files changed, 690 insertions, 0 deletions
diff --git a/sixel.c b/sixel.c
new file mode 100644
index 0000000..fef2442
--- /dev/null
+++ b/sixel.c
@@ -0,0 +1,690 @@
+// sixel.c (part of mintty)
+// originally written by kmiya@cluti (https://github.com/saitoha/sixel/blob/master/fromsixel.c)
+// Licensed under the terms of the GNU General Public License v3 or later.
+
+#include <stdlib.h>
+#include <string.h> /* memcpy */
+
+#include "st.h"
+#include "win.h"
+#include "sixel.h"
+#include "sixel_hls.h"
+
+#define SIXEL_RGB(r, g, b) ((255 << 24) + ((r) << 16) + ((g) << 8) + (b))
+#define SIXEL_PALVAL(n,a,m) (((n) * (a) + ((m) / 2)) / (m))
+#define SIXEL_XRGB(r,g,b) SIXEL_RGB(SIXEL_PALVAL(r, 255, 100), SIXEL_PALVAL(g, 255, 100), SIXEL_PALVAL(b, 255, 100))
+
+static sixel_color_t const sixel_default_color_table[] = {
+ SIXEL_XRGB( 0, 0, 0), /* 0 Black */
+ SIXEL_XRGB(20, 20, 80), /* 1 Blue */
+ SIXEL_XRGB(80, 13, 13), /* 2 Red */
+ SIXEL_XRGB(20, 80, 20), /* 3 Green */
+ SIXEL_XRGB(80, 20, 80), /* 4 Magenta */
+ SIXEL_XRGB(20, 80, 80), /* 5 Cyan */
+ SIXEL_XRGB(80, 80, 20), /* 6 Yellow */
+ SIXEL_XRGB(53, 53, 53), /* 7 Gray 50% */
+ SIXEL_XRGB(26, 26, 26), /* 8 Gray 25% */
+ SIXEL_XRGB(33, 33, 60), /* 9 Blue* */
+ SIXEL_XRGB(60, 26, 26), /* 10 Red* */
+ SIXEL_XRGB(33, 60, 33), /* 11 Green* */
+ SIXEL_XRGB(60, 33, 60), /* 12 Magenta* */
+ SIXEL_XRGB(33, 60, 60), /* 13 Cyan* */
+ SIXEL_XRGB(60, 60, 33), /* 14 Yellow* */
+ SIXEL_XRGB(80, 80, 80), /* 15 Gray 75% */
+};
+
+void
+scroll_images(int n) {
+ ImageList *im, *next;
+ int top = 0;
+
+ for (im = term.images; im; im = next) {
+ next = im->next;
+ im->y += n;
+
+ /* check if the current sixel has exceeded the maximum
+ * draw distance, and should therefore be deleted */
+ if (im->y < top) {
+ //fprintf(stderr, "im@0x%08x exceeded maximum distance\n");
+ delete_image(im);
+ }
+ }
+}
+
+void
+delete_image(ImageList *im)
+{
+ if (im->prev)
+ im->prev->next = im->next;
+ else
+ term.images = im->next;
+ if (im->next)
+ im->next->prev = im->prev;
+ if (im->pixmap)
+ XFreePixmap(xw.dpy, (Drawable)im->pixmap);
+ if (im->clipmask)
+ XFreePixmap(xw.dpy, (Drawable)im->clipmask);
+ free(im->pixels);
+ free(im);
+}
+
+static int
+set_default_color(sixel_image_t *image)
+{
+ int i;
+ int n;
+ int r;
+ int g;
+ int b;
+
+ /* palette initialization */
+ for (n = 1; n < 17; n++) {
+ image->palette[n] = sixel_default_color_table[n - 1];
+ }
+
+ /* colors 17-232 are a 6x6x6 color cube */
+ for (r = 0; r < 6; r++) {
+ for (g = 0; g < 6; g++) {
+ for (b = 0; b < 6; b++) {
+ image->palette[n++] = SIXEL_RGB(r * 51, g * 51, b * 51);
+ }
+ }
+ }
+
+ /* colors 233-256 are a grayscale ramp, intentionally leaving out */
+ for (i = 0; i < 24; i++) {
+ image->palette[n++] = SIXEL_RGB(i * 11, i * 11, i * 11);
+ }
+
+ for (; n < DECSIXEL_PALETTE_MAX; n++) {
+ image->palette[n] = SIXEL_RGB(255, 255, 255);
+ }
+
+ return (0);
+}
+
+static int
+sixel_image_init(
+ sixel_image_t *image,
+ int width,
+ int height,
+ int fgcolor,
+ int bgcolor,
+ int use_private_register)
+{
+ int status = (-1);
+ size_t size;
+
+ size = (size_t)(width * height) * sizeof(sixel_color_no_t);
+ image->width = width;
+ image->height = height;
+ image->data = (sixel_color_no_t *)malloc(size);
+ image->ncolors = 2;
+ image->use_private_register = use_private_register;
+
+ if (image->data == NULL) {
+ status = (-1);
+ goto end;
+ }
+ memset(image->data, 0, size);
+
+ image->palette[0] = bgcolor;
+
+ if (image->use_private_register)
+ image->palette[1] = fgcolor;
+
+ image->palette_modified = 0;
+
+ status = (0);
+
+end:
+ return status;
+}
+
+static int
+image_buffer_resize(
+ sixel_image_t *image,
+ int width,
+ int height)
+{
+ int status = (-1);
+ size_t size;
+ sixel_color_no_t *alt_buffer;
+ int n;
+ int min_height;
+
+ size = (size_t)(width * height) * sizeof(sixel_color_no_t);
+ alt_buffer = (sixel_color_no_t *)malloc(size);
+ if (alt_buffer == NULL) {
+ /* free source image */
+ free(image->data);
+ image->data = NULL;
+ status = (-1);
+ goto end;
+ }
+
+ min_height = height > image->height ? image->height: height;
+ if (width > image->width) { /* if width is extended */
+ for (n = 0; n < min_height; ++n) {
+ /* copy from source image */
+ memcpy(alt_buffer + width * n,
+ image->data + image->width * n,
+ (size_t)image->width * sizeof(sixel_color_no_t));
+ /* fill extended area with background color */
+ memset(alt_buffer + width * n + image->width,
+ 0,
+ (size_t)(width - image->width) * sizeof(sixel_color_no_t));
+ }
+ } else {
+ for (n = 0; n < min_height; ++n) {
+ /* copy from source image */
+ memcpy(alt_buffer + width * n,
+ image->data + image->width * n,
+ (size_t)width * sizeof(sixel_color_no_t));
+ }
+ }
+
+ if (height > image->height) { /* if height is extended */
+ /* fill extended area with background color */
+ memset(alt_buffer + width * image->height,
+ 0,
+ (size_t)(width * (height - image->height)) * sizeof(sixel_color_no_t));
+ }
+
+ /* free source image */
+ free(image->data);
+
+ image->data = alt_buffer;
+ image->width = width;
+ image->height = height;
+
+ status = (0);
+
+end:
+ return status;
+}
+
+static void
+sixel_image_deinit(sixel_image_t *image)
+{
+ if (image->data)
+ free(image->data);
+ image->data = NULL;
+}
+
+int
+sixel_parser_init(sixel_state_t *st,
+ int transparent,
+ sixel_color_t fgcolor, sixel_color_t bgcolor,
+ unsigned char use_private_register,
+ int cell_width, int cell_height)
+{
+ int status = (-1);
+
+ st->state = PS_DECSIXEL;
+ st->pos_x = 0;
+ st->pos_y = 0;
+ st->max_x = 0;
+ st->max_y = 0;
+ st->attributed_pan = 2;
+ st->attributed_pad = 1;
+ st->attributed_ph = 0;
+ st->attributed_pv = 0;
+ st->transparent = transparent;
+ st->repeat_count = 1;
+ st->color_index = 16;
+ st->grid_width = cell_width;
+ st->grid_height = cell_height;
+ st->nparams = 0;
+ st->param = 0;
+
+ /* buffer initialization */
+ status = sixel_image_init(&st->image, 1, 1, fgcolor, transparent ? 0 : bgcolor, use_private_register);
+
+ return status;
+}
+
+int
+sixel_parser_set_default_color(sixel_state_t *st)
+{
+ return set_default_color(&st->image);
+}
+
+int
+sixel_parser_finalize(sixel_state_t *st, ImageList **newimages, int cx, int cy, int cw, int ch)
+{
+ sixel_image_t *image = &st->image;
+ int x, y;
+ sixel_color_no_t *src;
+ sixel_color_t *dst, color;
+ int w, h;
+ int i, j, cols, numimages;
+ char trans;
+ ImageList *im, *next, *tail;
+
+ if (!image->data)
+ return -1;
+
+ if (++st->max_x < st->attributed_ph)
+ st->max_x = st->attributed_ph;
+
+ if (++st->max_y < st->attributed_pv)
+ st->max_y = st->attributed_pv;
+
+ if (image->use_private_register && image->ncolors > 2 && !image->palette_modified) {
+ if (set_default_color(image) < 0)
+ return -1;
+ }
+
+ w = MIN(st->max_x, image->width);
+ h = MIN(st->max_y, image->height);
+
+ if ((numimages = (h + ch-1) / ch) <= 0)
+ return -1;
+
+ cols = (w + cw-1) / cw;
+
+ *newimages = NULL, tail = NULL;
+ for (y = 0, i = 0; i < numimages; i++) {
+ if ((im = malloc(sizeof(ImageList)))) {
+ if (!tail) {
+ *newimages = tail = im;
+ im->prev = im->next = NULL;
+ } else {
+ tail->next = im;
+ im->prev = tail;
+ im->next = NULL;
+ tail = im;
+ }
+ im->x = cx;
+ im->y = cy + i;
+ im->cols = cols;
+ im->width = w;
+ im->height = MIN(h - ch * i, ch);
+ im->pixels = malloc(im->width * im->height * 4);
+ im->pixmap = NULL;
+ im->clipmask = NULL;
+ im->cw = cw;
+ im->ch = ch;
+ }
+ if (!im || !im->pixels) {
+ for (im = *newimages; im; im = next) {
+ next = im->next;
+ if (im->pixels)
+ free(im->pixels);
+ free(im);
+ }
+ *newimages = NULL;
+ return -1;
+ }
+ dst = (sixel_color_t *)im->pixels;
+ for (trans = 0, j = 0; j < im->height && y < h; j++, y++) {
+ src = st->image.data + image->width * y;
+ for (x = 0; x < w; x++) {
+ color = st->image.palette[*src++];
+ trans |= (color == 0);
+ *dst++ = color;
+ }
+ }
+ im->transparent = (st->transparent && trans);
+ }
+
+ return numimages;
+}
+
+/* convert sixel data into indexed pixel bytes and palette data */
+int
+sixel_parser_parse(sixel_state_t *st, const unsigned char *p, size_t len)
+{
+ int n = 0;
+ int i;
+ int x;
+ int y;
+ int bits;
+ int sx;
+ int sy;
+ int c;
+ int pos;
+ int width;
+ const unsigned char *p0 = p, *p2 = p + len;
+ sixel_image_t *image = &st->image;
+ sixel_color_no_t *data, color_index;
+
+ if (!image->data)
+ st->state = PS_ERROR;
+
+ while (p < p2) {
+ switch (st->state) {
+ case PS_ESC:
+ goto end;
+
+ case PS_DECSIXEL:
+ switch (*p) {
+ case '\x1b':
+ st->state = PS_ESC;
+ break;
+ case '"':
+ st->param = 0;
+ st->nparams = 0;
+ st->state = PS_DECGRA;
+ p++;
+ break;
+ case '!':
+ st->param = 0;
+ st->nparams = 0;
+ st->state = PS_DECGRI;
+ p++;
+ break;
+ case '#':
+ st->param = 0;
+ st->nparams = 0;
+ st->state = PS_DECGCI;
+ p++;
+ break;
+ case '$':
+ /* DECGCR Graphics Carriage Return */
+ st->pos_x = 0;
+ p++;
+ break;
+ case '-':
+ /* DECGNL Graphics Next Line */
+ st->pos_x = 0;
+ if (st->pos_y < DECSIXEL_HEIGHT_MAX - 5 - 6)
+ st->pos_y += 6;
+ else
+ st->pos_y = DECSIXEL_HEIGHT_MAX + 1;
+ p++;
+ break;
+ default:
+ if (*p >= '?' && *p <= '~') { /* sixel characters */
+ if ((image->width < (st->pos_x + st->repeat_count) || image->height < (st->pos_y + 6))
+ && image->width < DECSIXEL_WIDTH_MAX && image->height < DECSIXEL_HEIGHT_MAX) {
+ sx = image->width * 2;
+ sy = image->height * 2;
+ while (sx < (st->pos_x + st->repeat_count) || sy < (st->pos_y + 6)) {
+ sx *= 2;
+ sy *= 2;
+ }
+
+ sx = MIN(sx, DECSIXEL_WIDTH_MAX);
+ sy = MIN(sy, DECSIXEL_HEIGHT_MAX);
+
+ if (image_buffer_resize(image, sx, sy) < 0) {
+ perror("sixel_parser_parse() failed");
+ st->state = PS_ERROR;
+ p++;
+ break;
+ }
+ }
+
+ if (st->color_index > image->ncolors)
+ image->ncolors = st->color_index;
+
+ if (st->pos_x + st->repeat_count > image->width)
+ st->repeat_count = image->width - st->pos_x;
+
+ if (st->repeat_count > 0 && st->pos_y + 5 < image->height) {
+ bits = *p - '?';
+ if (bits != 0) {
+ data = image->data + image->width * st->pos_y + st->pos_x;
+ width = image->width;
+ color_index = st->color_index;
+ if (st->repeat_count <= 1) {
+ if (bits & 0x01)
+ *data = color_index, n = 0;
+ data += width;
+ if (bits & 0x02)
+ *data = color_index, n = 1;
+ data += width;
+ if (bits & 0x04)
+ *data = color_index, n = 2;
+ data += width;
+ if (bits & 0x08)
+ *data = color_index, n = 3;
+ data += width;
+ if (bits & 0x10)
+ *data = color_index, n = 4;
+ if (bits & 0x20)
+ data[width] = color_index, n = 5;
+ if (st->max_x < st->pos_x)
+ st->max_x = st->pos_x;
+ } else {
+ /* st->repeat_count > 1 */
+ for (i = 0; bits; bits >>= 1, i++, data += width) {
+ if (bits & 1) {
+ data[0] = color_index;
+ data[1] = color_index;
+ for (x = 2; x < st->repeat_count; x++)
+ data[x] = color_index;
+ n = i;
+ }
+ }
+ if (st->max_x < (st->pos_x + st->repeat_count - 1))
+ st->max_x = st->pos_x + st->repeat_count - 1;
+ }
+ if (st->max_y < (st->pos_y + n))
+ st->max_y = st->pos_y + n;
+ }
+ }
+ if (st->repeat_count > 0)
+ st->pos_x += st->repeat_count;
+ st->repeat_count = 1;
+ }
+ p++;
+ break;
+ }
+ break;
+
+ case PS_DECGRA:
+ /* DECGRA Set Raster Attributes " Pan; Pad; Ph; Pv */
+ switch (*p) {
+ case '\x1b':
+ st->state = PS_ESC;
+ break;
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9':
+ st->param = st->param * 10 + *p - '0';
+ st->param = MIN(st->param, DECSIXEL_PARAMVALUE_MAX);
+ p++;
+ break;
+ case ';':
+ if (st->nparams < DECSIXEL_PARAMS_MAX)
+ st->params[st->nparams++] = st->param;
+ st->param = 0;
+ p++;
+ break;
+ default:
+ if (st->nparams < DECSIXEL_PARAMS_MAX)
+ st->params[st->nparams++] = st->param;
+ if (st->nparams > 0)
+ st->attributed_pad = st->params[0];
+ if (st->nparams > 1)
+ st->attributed_pan = st->params[1];
+ if (st->nparams > 2 && st->params[2] > 0)
+ st->attributed_ph = st->params[2];
+ if (st->nparams > 3 && st->params[3] > 0)
+ st->attributed_pv = st->params[3];
+
+ if (st->attributed_pan <= 0)
+ st->attributed_pan = 1;
+ if (st->attributed_pad <= 0)
+ st->attributed_pad = 1;
+
+ if (image->width < st->attributed_ph ||
+ image->height < st->attributed_pv) {
+ sx = MAX(image->width, st->attributed_ph);
+ sy = MAX(image->height, st->attributed_pv);
+
+ /* the height of the image buffer must be divisible by 6
+ * to avoid unnecessary resizing of the image buffer when
+ * parsing the last sixel line */
+ sy = (sy + 5) / 6 * 6;
+
+ sx = MIN(sx, DECSIXEL_WIDTH_MAX);
+ sy = MIN(sy, DECSIXEL_HEIGHT_MAX);
+
+ if (image_buffer_resize(image, sx, sy) < 0) {
+ perror("sixel_parser_parse() failed");
+ st->state = PS_ERROR;
+ break;
+ }
+ }
+ st->state = PS_DECSIXEL;
+ st->param = 0;
+ st->nparams = 0;
+ }
+ break;
+
+ case PS_DECGRI:
+ /* DECGRI Graphics Repeat Introducer ! Pn Ch */
+ switch (*p) {
+ case '\x1b':
+ st->state = PS_ESC;
+ break;
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9':
+ st->param = st->param * 10 + *p - '0';
+ st->param = MIN(st->param, DECSIXEL_PARAMVALUE_MAX);
+ p++;
+ break;
+ default:
+ st->repeat_count = MAX(st->param, 1);
+ st->state = PS_DECSIXEL;
+ st->param = 0;
+ st->nparams = 0;
+ break;
+ }
+ break;
+
+ case PS_DECGCI:
+ /* DECGCI Graphics Color Introducer # Pc; Pu; Px; Py; Pz */
+ switch (*p) {
+ case '\x1b':
+ st->state = PS_ESC;
+ break;
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9':
+ st->param = st->param * 10 + *p - '0';
+ st->param = MIN(st->param, DECSIXEL_PARAMVALUE_MAX);
+ p++;
+ break;
+ case ';':
+ if (st->nparams < DECSIXEL_PARAMS_MAX)
+ st->params[st->nparams++] = st->param;
+ st->param = 0;
+ p++;
+ break;
+ default:
+ st->state = PS_DECSIXEL;
+ if (st->nparams < DECSIXEL_PARAMS_MAX)
+ st->params[st->nparams++] = st->param;
+ st->param = 0;
+
+ if (st->nparams > 0) {
+ st->color_index = 1 + st->params[0]; /* offset 1(background color) added */
+ if (st->color_index < 0)
+ st->color_index = 0;
+ else if (st->color_index >= DECSIXEL_PALETTE_MAX)
+ st->color_index = DECSIXEL_PALETTE_MAX - 1;
+ }
+
+ if (st->nparams > 4) {
+ st->image.palette_modified = 1;
+ if (st->params[1] == 1) {
+ /* HLS */
+ st->params[2] = MIN(st->params[2], 360);
+ st->params[3] = MIN(st->params[3], 100);
+ st->params[4] = MIN(st->params[4], 100);
+ image->palette[st->color_index]
+ = hls_to_rgb(st->params[2], st->params[3], st->params[4]);
+ } else if (st->params[1] == 2) {
+ /* RGB */
+ st->params[2] = MIN(st->params[2], 100);
+ st->params[3] = MIN(st->params[3], 100);
+ st->params[4] = MIN(st->params[4], 100);
+ image->palette[st->color_index]
+ = SIXEL_XRGB(st->params[2], st->params[3], st->params[4]);
+ }
+ }
+ break;
+ }
+ break;
+
+ case PS_ERROR:
+ if (*p == '\x1b') {
+ st->state = PS_ESC;
+ goto end;
+ }
+ p++;
+ break;
+ default:
+ break;
+ }
+ }
+
+end:
+ return p - p0;
+}
+
+void
+sixel_parser_deinit(sixel_state_t *st)
+{
+ if (st)
+ sixel_image_deinit(&st->image);
+}
+
+Pixmap
+sixel_create_clipmask(char *pixels, int width, int height)
+{
+ char c, *clipdata, *dst;
+ int b, i, n, y, w;
+ int msb = (XBitmapBitOrder(xw.dpy) == MSBFirst);
+ sixel_color_t *src = (sixel_color_t *)pixels;
+ Pixmap clipmask;
+
+ clipdata = dst = malloc((width+7)/8 * height);
+ if (!clipdata)
+ return (Pixmap)None;
+
+ for (y = 0; y < height; y++) {
+ for (w = width; w > 0; w -= n) {
+ n = MIN(w, 8);
+ if (msb) {
+ for (b = 0x80, c = 0, i = 0; i < n; i++, b >>= 1)
+ c |= (*src++) ? b : 0;
+ } else {
+ for (b = 0x01, c = 0, i = 0; i < n; i++, b <<= 1)
+ c |= (*src++) ? b : 0;
+ }
+ *dst++ = c;
+ }
+ }
+
+ clipmask = XCreateBitmapFromData(xw.dpy, xw.win, clipdata, width, height);
+ free(clipdata);
+ return clipmask;
+}
generated by cgit v1.2.3 (git 2.46.0) at 2026-03-01 13:27:29 +0000