X-Git-Url: http://git.imager.perl.org/imager.git/blobdiff_plain/7bd0a037b16d4c5831a07b1efc11a098b3e4a638..a87997b2f901c06ea67e73d89558aa376f64019b:/bmp.c diff --git a/bmp.c b/bmp.c index 76c7e600..61a7d82d 100644 --- a/bmp.c +++ b/bmp.c @@ -1,3 +1,4 @@ +#define IMAGER_NO_CONTEXT #include #include "imageri.h" @@ -35,6 +36,11 @@ Reads and writes Windows BMP files. #define BMPRLE_ENDOFBMP 1 #define BMPRLE_DELTA 2 +#define SIGNBIT32 ((i_upacked_t)1U << 31) +#define SIGNBIT16 ((i_upacked_t)1U << 15) + +#define SIGNMAX32 ((1UL << 31) - 1) + static int read_packed(io_glue *ig, char *format, ...); static int write_packed(io_glue *ig, char *format, ...); static int write_bmphead(io_glue *ig, i_img *im, int bit_count, @@ -54,6 +60,11 @@ static i_img *read_direct_bmp(io_glue *ig, int xsize, int ysize, int bit_count, int clr_used, int compression, long offbits, int allow_incomplete); +/* used for the read_packed() and write_packed() functions, an integer + * type */ +typedef long i_packed_t; +typedef unsigned long i_upacked_t; + /* =item i_writebmp_wiol(im, io_glue) @@ -66,7 +77,7 @@ Never compresses the image. */ int i_writebmp_wiol(i_img *im, io_glue *ig) { - io_glue_commit_types(ig); + dIMCTXim(im); i_clear_error(); /* pick a format */ @@ -103,17 +114,17 @@ BI_BITFIELDS images too, but I need a test image. i_img * i_readbmp_wiol(io_glue *ig, int allow_incomplete) { - int b_magic, m_magic, filesize, res1, res2, infohead_size; - int xsize, ysize, planes, bit_count, compression, size_image, xres, yres; - int clr_used, clr_important, offbits; + i_packed_t b_magic, m_magic, filesize, res1, res2, infohead_size; + i_packed_t xsize, ysize, planes, bit_count, compression, size_image, xres, yres; + i_packed_t clr_used, clr_important, offbits; i_img *im; + dIMCTXio(ig); - mm_log((1, "i_readbmp_wiol(ig %p)\n", ig)); + im_log((aIMCTX, 1, "i_readbmp_wiol(ig %p)\n", ig)); - io_glue_commit_types(ig); i_clear_error(); - if (!read_packed(ig, "CCVvvVVVVvvVVVVVV", &b_magic, &m_magic, &filesize, + if (!read_packed(ig, "CCVvvVVV!V!vvVVVVVV", &b_magic, &m_magic, &filesize, &res1, &res2, &offbits, &infohead_size, &xsize, &ysize, &planes, &bit_count, &compression, &size_image, &xres, &yres, @@ -127,14 +138,15 @@ i_readbmp_wiol(io_glue *ig, int allow_incomplete) { return 0; } - mm_log((1, " bmp header: filesize %d offbits %d xsize %d ysize %d planes %d " + im_log((aIMCTX, 1, " bmp header: filesize %d offbits %d xsize %d ysize %d planes %d " "bit_count %d compression %d size %d xres %d yres %d clr_used %d " - "clr_important %d\n", filesize, offbits, xsize, ysize, planes, - bit_count, compression, size_image, xres, yres, clr_used, - clr_important)); + "clr_important %d\n", (int)filesize, (int)offbits, (int)xsize, + (int)ysize, (int)planes, (int)bit_count, (int)compression, + (int)size_image, (int)xres, (int)yres, (int)clr_used, + (int)clr_important)); if (!i_int_check_image_file_limits(xsize, abs(ysize), 3, sizeof(i_sample_t))) { - mm_log((1, "i_readbmp_wiol: image size exceeds limits\n")); + im_log((aIMCTX, 1, "i_readbmp_wiol: image size exceeds limits\n")); return NULL; } @@ -162,7 +174,7 @@ i_readbmp_wiol(io_glue *ig, int allow_incomplete) { break; default: - i_push_errorf(0, "unknown bit count for BMP file (%d)", bit_count); + im_push_errorf(aIMCTX, 0, "unknown bit count for BMP file (%d)", (int)bit_count); return NULL; } @@ -206,52 +218,69 @@ Returns non-zero if all of the arguments were read. =cut */ -static -int read_packed(io_glue *ig, char *format, ...) { +static int +read_packed(io_glue *ig, char *format, ...) { unsigned char buf[4]; va_list ap; - int *p; + i_packed_t *p; + i_packed_t work; + int code; + int shrieking; /* format code has a ! flag */ va_start(ap, format); while (*format) { - p = va_arg(ap, int *); + p = va_arg(ap, i_packed_t *); - switch (*format) { + code = *format++; + shrieking = *format == '!'; + if (shrieking) ++format; + + switch (code) { case 'v': - if (ig->readcb(ig, buf, 2) != 2) + if (i_io_read(ig, buf, 2) != 2) return 0; - *p = buf[0] + (buf[1] << 8); + work = buf[0] + ((i_packed_t)buf[1] << 8); + if (shrieking) + *p = (work ^ SIGNBIT16) - SIGNBIT16; + else + *p = work; break; case 'V': - if (ig->readcb(ig, buf, 4) != 4) + if (i_io_read(ig, buf, 4) != 4) return 0; - *p = buf[0] + (buf[1] << 8) + (buf[2] << 16) + (buf[3] << 24); + work = buf[0] + (buf[1] << 8) + ((i_packed_t)buf[2] << 16) + ((i_packed_t)buf[3] << 24); + if (shrieking) + *p = (work ^ SIGNBIT32) - SIGNBIT32; + else + *p = work; break; case 'C': - if (ig->readcb(ig, buf, 1) != 1) + if (i_io_read(ig, buf, 1) != 1) return 0; *p = buf[0]; break; case 'c': - if (ig->readcb(ig, buf, 1) != 1) + if (i_io_read(ig, buf, 1) != 1) return 0; *p = (char)buf[0]; break; case '3': /* extension - 24-bit number */ - if (ig->readcb(ig, buf, 3) != 3) + if (i_io_read(ig, buf, 3) != 3) return 0; - *p = buf[0] + (buf[1] << 8) + (buf[2] << 16); + *p = buf[0] + (buf[1] << 8) + ((i_packed_t)buf[2] << 16); break; default: - i_fatal(1, "Unknown read_packed format code 0x%02x", *format); + { + dIMCTXio(ig); + im_fatal(aIMCTX, 1, "Unknown read_packed format code 0x%02x", code); + } } - ++format; } return 1; } @@ -275,13 +304,13 @@ write_packed(io_glue *ig, char *format, ...) { va_start(ap, format); while (*format) { - i = va_arg(ap, unsigned int); + i = va_arg(ap, i_upacked_t); switch (*format) { case 'v': buf[0] = i & 255; buf[1] = i / 256; - if (ig->writecb(ig, buf, 2) == -1) + if (i_io_write(ig, buf, 2) == -1) return 0; break; @@ -290,19 +319,22 @@ write_packed(io_glue *ig, char *format, ...) { buf[1] = (i >> 8) & 0xFF; buf[2] = (i >> 16) & 0xFF; buf[3] = (i >> 24) & 0xFF; - if (ig->writecb(ig, buf, 4) == -1) + if (i_io_write(ig, buf, 4) == -1) return 0; break; case 'C': case 'c': buf[0] = i & 0xFF; - if (ig->writecb(ig, buf, 1) == -1) + if (i_io_write(ig, buf, 1) == -1) return 0; break; default: - i_fatal(1, "Unknown write_packed format code 0x%02x", *format); + { + dIMCTXio(ig); + im_fatal(aIMCTX, 1, "Unknown write_packed format code 0x%02x", *format); + } } ++format; } @@ -327,6 +359,12 @@ int write_bmphead(io_glue *ig, i_img *im, int bit_count, int data_size) { int got_xres, got_yres, aspect_only; int colors_used = 0; int offset = FILEHEAD_SIZE + INFOHEAD_SIZE; + dIMCTXim(im); + + if (im->xsize > SIGNMAX32 || im->ysize > SIGNMAX32) { + i_push_error(0, "image too large to write to BMP"); + return 0; + } got_xres = i_tags_get_float(&im->tags, "i_xres", 0, &xres); got_yres = i_tags_get_float(&im->tags, "i_yres", 0, &yres); @@ -365,10 +403,15 @@ int write_bmphead(io_glue *ig, i_img *im, int bit_count, int data_size) { offset += 4 * colors_used; } - if (!write_packed(ig, "CCVvvVVVVvvVVVVVV", 'B', 'M', data_size+offset, - 0, 0, offset, INFOHEAD_SIZE, im->xsize, im->ysize, 1, - bit_count, BI_RGB, 0, (int)(xres+0.5), (int)(yres+0.5), - colors_used, colors_used)){ + if (!write_packed(ig, "CCVvvVVVVvvVVVVVV", 'B', 'M', + (i_upacked_t)(data_size+offset), + (i_upacked_t)0, (i_upacked_t)0, (i_upacked_t)offset, + (i_upacked_t)INFOHEAD_SIZE, (i_upacked_t)im->xsize, + (i_upacked_t)im->ysize, (i_upacked_t)1, + (i_upacked_t)bit_count, (i_upacked_t)BI_RGB, + (i_upacked_t)data_size, + (i_upacked_t)(xres+0.5), (i_upacked_t)(yres+0.5), + (i_upacked_t)colors_used, (i_upacked_t)colors_used)){ i_push_error(0, "cannot write bmp header"); return 0; } @@ -379,15 +422,16 @@ int write_bmphead(io_glue *ig, i_img *im, int bit_count, int data_size) { for (i = 0; i < colors_used; ++i) { i_getcolors(im, i, &c, 1); if (im->channels >= 3) { - if (!write_packed(ig, "CCCC", c.channel[2], c.channel[1], - c.channel[0], 0)) { + if (!write_packed(ig, "CCCC", (i_upacked_t)(c.channel[2]), + (i_upacked_t)(c.channel[1]), + (i_upacked_t)(c.channel[0]), (i_upacked_t)0)) { i_push_error(0, "cannot write palette entry"); return 0; } } else { - if (!write_packed(ig, "CCCC", c.channel[0], c.channel[0], - c.channel[0], 0)) { + i_upacked_t v = c.channel[0]; + if (!write_packed(ig, "CCCC", v, v, v, 0)) { i_push_error(0, "cannot write palette entry"); return 0; } @@ -417,6 +461,7 @@ write_1bit_data(io_glue *ig, i_img *im) { int line_size = (im->xsize+7) / 8; int x, y; int unpacked_size; + dIMCTXim(im); /* round up to nearest multiple of four */ line_size = (line_size + 3) / 4 * 4; @@ -455,7 +500,7 @@ write_1bit_data(io_glue *ig, i_img *im) { if (mask != 0x80) { *out++ = byte; } - if (ig->writecb(ig, packed, line_size) < 0) { + if (i_io_write(ig, packed, line_size) < 0) { myfree(packed); myfree(line); i_push_error(0, "writing 1 bit/pixel packed data"); @@ -465,7 +510,8 @@ write_1bit_data(io_glue *ig, i_img *im) { myfree(packed); myfree(line); - ig->closecb(ig); + if (i_io_close(ig)) + return 0; return 1; } @@ -487,6 +533,7 @@ write_4bit_data(io_glue *ig, i_img *im) { int line_size = (im->xsize+1) / 2; int x, y; int unpacked_size; + dIMCTXim(im); /* round up to nearest multiple of four */ line_size = (line_size + 3) / 4 * 4; @@ -514,7 +561,7 @@ write_4bit_data(io_glue *ig, i_img *im) { for (x = 0; x < im->xsize; x += 2) { *out++ = (line[x] << 4) + line[x+1]; } - if (ig->writecb(ig, packed, line_size) < 0) { + if (i_io_write(ig, packed, line_size) < 0) { myfree(packed); myfree(line); i_push_error(0, "writing 4 bit/pixel packed data"); @@ -524,7 +571,8 @@ write_4bit_data(io_glue *ig, i_img *im) { myfree(packed); myfree(line); - ig->closecb(ig); + if (i_io_close(ig)) + return 0; return 1; } @@ -544,6 +592,7 @@ write_8bit_data(io_glue *ig, i_img *im) { int line_size = im->xsize; int y; int unpacked_size; + dIMCTXim(im); /* round up to nearest multiple of four */ line_size = (line_size + 3) / 4 * 4; @@ -562,7 +611,7 @@ write_8bit_data(io_glue *ig, i_img *im) { for (y = im->ysize-1; y >= 0; --y) { i_gpal(im, 0, im->xsize, y, line); - if (ig->writecb(ig, line, line_size) < 0) { + if (i_io_write(ig, line, line_size) < 0) { myfree(line); i_push_error(0, "writing 8 bit/pixel packed data"); return 0; @@ -570,7 +619,8 @@ write_8bit_data(io_glue *ig, i_img *im) { } myfree(line); - ig->closecb(ig); + if (i_io_close(ig)) + return 0; return 1; } @@ -590,6 +640,7 @@ write_24bit_data(io_glue *ig, i_img *im) { int y; int line_size = 3 * im->xsize; i_color bg; + dIMCTXim(im); i_get_file_background(im, &bg); @@ -616,7 +667,7 @@ write_24bit_data(io_glue *ig, i_img *im) { samplep[0] = tmp; samplep += 3; } - if (ig->writecb(ig, samples, line_size) < 0) { + if (i_io_write(ig, samples, line_size) < 0) { i_push_error(0, "writing image data"); myfree(samples); return 0; @@ -624,7 +675,8 @@ write_24bit_data(io_glue *ig, i_img *im) { } myfree(samples); - ig->closecb(ig); + if (i_io_close(ig)) + return 0; return 1; } @@ -641,8 +693,9 @@ Returns non-zero on success. static int read_bmp_pal(io_glue *ig, i_img *im, int count) { int i; - int r, g, b, x; + i_packed_t r, g, b, x; i_color c; + dIMCTXio(ig); for (i = 0; i < count; ++i) { if (!read_packed(ig, "CCCC", &b, &g, &r, &x)) { @@ -681,13 +734,14 @@ read_1bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, int bit; unsigned char *in; long base_offset; + dIMCTXio(ig); if (compression != BI_RGB) { - i_push_errorf(0, "unknown 1-bit BMP compression (%d)", compression); + im_push_errorf(aIMCTX, 0, "unknown 1-bit BMP compression (%d)", compression); return NULL; } - if (xsize + 8 < xsize) { /* if there was overflow */ + if ((i_img_dim)((i_img_dim_u)xsize + 8) < xsize) { /* if there was overflow */ /* we check with 8 because we allocate that much for the decoded line buffer */ i_push_error(0, "integer overflow during memory allocation"); @@ -714,13 +768,13 @@ read_1bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, if (!clr_used) clr_used = 2; if (clr_used < 0 || clr_used > 2) { - i_push_errorf(0, "out of range colors used (%d)", clr_used); + im_push_errorf(aIMCTX, 0, "out of range colors used (%d)", clr_used); return NULL; } base_offset = FILEHEAD_SIZE + INFOHEAD_SIZE + clr_used * 4; if (offbits < base_offset) { - i_push_errorf(0, "image data offset too small (%ld)", offbits); + im_push_errorf(aIMCTX, 0, "image data offset too small (%ld)", offbits); return NULL; } @@ -737,7 +791,7 @@ read_1bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, rare */ char buffer; while (base_offset < offbits) { - if (ig->readcb(ig, &buffer, 1) != 1) { + if (i_io_read(ig, &buffer, 1) != 1) { i_img_destroy(im); i_push_error(0, "failed skipping to image data offset"); return NULL; @@ -751,7 +805,7 @@ read_1bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, packed = mymalloc(line_size); /* checked 29jun05 tonyc */ line = mymalloc(xsize+8); /* checked 29jun05 tonyc */ while (y != lasty) { - if (ig->readcb(ig, packed, line_size) != line_size) { + if (i_io_read(ig, packed, line_size) != line_size) { myfree(packed); myfree(line); if (allow_incomplete) { @@ -809,6 +863,7 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, int size, i; long base_offset; int starty; + dIMCTXio(ig); /* line_size is going to be smaller than xsize in most cases (and when it's not, xsize is itself small), and hence not overflow */ @@ -831,13 +886,13 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, clr_used = 16; if (clr_used > 16 || clr_used < 0) { - i_push_errorf(0, "out of range colors used (%d)", clr_used); + im_push_errorf(aIMCTX, 0, "out of range colors used (%d)", clr_used); return NULL; } base_offset = FILEHEAD_SIZE + INFOHEAD_SIZE + clr_used * 4; if (offbits < base_offset) { - i_push_errorf(0, "image data offset too small (%ld)", offbits); + im_push_errorf(aIMCTX, 0, "image data offset too small (%ld)", offbits); return NULL; } @@ -854,7 +909,7 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, rare */ char buffer; while (base_offset < offbits) { - if (ig->readcb(ig, &buffer, 1) != 1) { + if (i_io_read(ig, &buffer, 1) != 1) { i_img_destroy(im); i_push_error(0, "failed skipping to image data offset"); return NULL; @@ -872,7 +927,7 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, if (compression == BI_RGB) { i_tags_add(&im->tags, "bmp_compression_name", 0, "BI_RGB", -1, 0); while (y != lasty) { - if (ig->readcb(ig, packed, line_size) != line_size) { + if (i_io_read(ig, packed, line_size) != line_size) { myfree(packed); myfree(line); if (allow_incomplete) { @@ -902,12 +957,13 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, else if (compression == BI_RLE4) { int read_size; int count; + i_img_dim xlimit = (xsize + 1) / 2 * 2; /* rounded up */ i_tags_add(&im->tags, "bmp_compression_name", 0, "BI_RLE4", -1, 0); x = 0; while (1) { /* there's always at least 2 bytes in a sequence */ - if (ig->readcb(ig, packed, 2) != 2) { + if (i_io_read(ig, packed, 2) != 2) { myfree(packed); myfree(line); if (allow_incomplete) { @@ -922,23 +978,24 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, } } else if (packed[0]) { - if (x + packed[0] > xsize) { + int count = packed[0]; + if (x + count > xlimit) { /* this file is corrupt */ myfree(packed); myfree(line); i_push_error(0, "invalid data during decompression"); + im_log((aIMCTX, 1, "read 4-bit: scanline overflow x %d + count %d vs xlimit %d (y %d)\n", + (int)x, count, (int)xlimit, (int)y)); i_img_destroy(im); return NULL; } - line[0] = packed[1] >> 4; - line[1] = packed[1] & 0x0F; - for (i = 0; i < packed[0]; i += 2) { - if (i < packed[0]-1) - i_ppal(im, x, x+2, y, line); - else - i_ppal(im, x, x+(packed[0]-i), y, line); - x += 2; - } + /* fill in the line */ + for (i = 0; i < count; i += 2) + line[i] = packed[1] >> 4; + for (i = 1; i < count; i += 2) + line[i] = packed[1] & 0x0F; + i_ppal(im, x, x+count, y, line); + x += count; } else { switch (packed[1]) { case BMPRLE_ENDOFLINE: @@ -952,7 +1009,7 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, return im; case BMPRLE_DELTA: - if (ig->readcb(ig, packed, 2) != 2) { + if (i_io_read(ig, packed, 2) != 2) { myfree(packed); myfree(line); if (allow_incomplete) { @@ -972,17 +1029,19 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, default: count = packed[1]; - if (x + count > xsize) { + if (x + count > xlimit) { /* this file is corrupt */ myfree(packed); myfree(line); i_push_error(0, "invalid data during decompression"); + im_log((aIMCTX, 1, "read 4-bit: scanline overflow (unpacked) x %d + count %d vs xlimit %d (y %d)\n", + (int)x, count, (int)xlimit, (int)y)); i_img_destroy(im); return NULL; } size = (count + 1) / 2; read_size = (size+1) / 2 * 2; - if (ig->readcb(ig, packed, read_size) != read_size) { + if (i_io_read(ig, packed, read_size) != read_size) { myfree(packed); myfree(line); if (allow_incomplete) { @@ -1010,7 +1069,7 @@ read_4bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, else { /*if (compression == BI_RLE4) {*/ myfree(packed); myfree(line); - i_push_errorf(0, "unknown 4-bit BMP compression (%d)", compression); + im_push_errorf(aIMCTX, 0, "unknown 4-bit BMP compression (%d)", compression); i_img_destroy(im); return NULL; } @@ -1035,6 +1094,7 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, i_palidx *line; int line_size = xsize; long base_offset; + dIMCTXio(ig); line_size = (line_size+3) / 4 * 4; if (line_size < xsize) { /* if it overflowed (unlikely, but check) */ @@ -1058,13 +1118,13 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, if (!clr_used) clr_used = 256; if (clr_used > 256 || clr_used < 0) { - i_push_errorf(0, "out of range colors used (%d)", clr_used); + im_push_errorf(aIMCTX, 0, "out of range colors used (%d)", clr_used); return NULL; } base_offset = FILEHEAD_SIZE + INFOHEAD_SIZE + clr_used * 4; if (offbits < base_offset) { - i_push_errorf(0, "image data offset too small (%ld)", offbits); + im_push_errorf(aIMCTX, 0, "image data offset too small (%ld)", offbits); return NULL; } @@ -1081,7 +1141,7 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, rare */ char buffer; while (base_offset < offbits) { - if (ig->readcb(ig, &buffer, 1) != 1) { + if (i_io_read(ig, &buffer, 1) != 1) { i_img_destroy(im); i_push_error(0, "failed skipping to image data offset"); return NULL; @@ -1094,7 +1154,7 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, if (compression == BI_RGB) { i_tags_add(&im->tags, "bmp_compression_name", 0, "BI_RGB", -1, 0); while (y != lasty) { - if (ig->readcb(ig, line, line_size) != line_size) { + if (i_io_read(ig, line, line_size) != line_size) { myfree(line); if (allow_incomplete) { i_tags_setn(&im->tags, "i_incomplete", 1); @@ -1121,7 +1181,7 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, x = 0; while (1) { /* there's always at least 2 bytes in a sequence */ - if (ig->readcb(ig, packed, 2) != 2) { + if (i_io_read(ig, packed, 2) != 2) { myfree(line); if (allow_incomplete) { i_tags_setn(&im->tags, "i_incomplete", 1); @@ -1157,7 +1217,7 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, return im; case BMPRLE_DELTA: - if (ig->readcb(ig, packed, 2) != 2) { + if (i_io_read(ig, packed, 2) != 2) { myfree(line); if (allow_incomplete) { i_tags_setn(&im->tags, "i_incomplete", 1); @@ -1185,7 +1245,7 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, return NULL; } read_size = (count+1) / 2 * 2; - if (ig->readcb(ig, line, read_size) != read_size) { + if (i_io_read(ig, line, read_size) != read_size) { myfree(line); if (allow_incomplete) { i_tags_setn(&im->tags, "i_incomplete", 1); @@ -1207,7 +1267,7 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, } else { myfree(line); - i_push_errorf(0, "unknown 8-bit BMP compression (%d)", compression); + im_push_errorf(aIMCTX, 0, "unknown 8-bit BMP compression (%d)", compression); i_img_destroy(im); return NULL; } @@ -1218,23 +1278,42 @@ read_8bit_bmp(io_glue *ig, int xsize, int ysize, int clr_used, struct bm_masks { unsigned masks[3]; int shifts[3]; + int bits[3]; }; static struct bm_masks std_masks[] = { { /* 16-bit */ - { 0770000, 00007700, 00000077, }, - { 10, 4, -2, }, + { 0076000, 00001740, 00000037, }, + { 10, 5, 0, }, + { 5, 5, 5, } }, { /* 24-bit */ { 0xFF0000, 0x00FF00, 0x0000FF, }, { 16, 8, 0, }, + { 8, 8, 8, }, }, { /* 32-bit */ { 0xFF0000, 0x00FF00, 0x0000FF, }, { 16, 8, 0, }, + { 8, 8, 8, }, }, }; +/* multiplier and shift for converting from N bits to 8 bits */ +struct bm_sampconverts { + int mult; + int shift; +}; +static struct bm_sampconverts samp_converts[] = { + { 0xff, 0 }, /* 1 bit samples */ + { 0x55, 0 }, + { 0111, 1 }, + { 0x11, 0 }, + { 0x21, 2 }, + { 0x41, 4 }, + { 0x81, 6 } /* 7 bit samples */ +}; + /* =item read_direct_bmp(ig, xsize, ysize, bit_count, clr_used, compression, allow_incomplete) @@ -1261,6 +1340,7 @@ read_direct_bmp(io_glue *ig, int xsize, int ysize, int bit_count, const char *compression_name; int bytes; long base_offset = FILEHEAD_SIZE + INFOHEAD_SIZE; + dIMCTXio(ig); unpack_code[0] = *("v3V"+pix_size-2); unpack_code[1] = '\0'; @@ -1288,7 +1368,7 @@ read_direct_bmp(io_glue *ig, int xsize, int ysize, int bit_count, /* there's a potential "palette" after the header */ for (i = 0; i < clr_used; ++clr_used) { char buf[4]; - if (ig->readcb(ig, buf, 4) != 4) { + if (i_io_read(ig, buf, 4) != 4) { i_push_error(0, "skipping colors"); return 0; } @@ -1296,32 +1376,47 @@ read_direct_bmp(io_glue *ig, int xsize, int ysize, int bit_count, } } else if (compression == BI_BITFIELDS) { - int pos, bit; + int pos; + unsigned bits; compression_name = "BI_BITFIELDS"; for (i = 0; i < 3; ++i) { - if (!read_packed(ig, "V", masks.masks+i)) { + i_packed_t rmask; + if (!read_packed(ig, "V", &rmask)) { i_push_error(0, "reading pixel masks"); return 0; } + if (rmask == 0) { + im_push_errorf(aIMCTX, 0, "Zero mask for channel %d", i); + return NULL; + } + masks.masks[i] = rmask; /* work out a shift for the mask */ pos = 0; - bit = masks.masks[i] & -masks.masks[i]; - while (bit) { + bits = masks.masks[i]; + while (!(bits & 1)) { ++pos; - bit >>= 1; + bits >>= 1; } - masks.shifts[i] = pos - 8; + masks.shifts[i] = pos; + pos = 0; + while (bits & 1) { + ++pos; + bits >>= 1; + } + masks.bits[i] = pos; + /*fprintf(stderr, "%d: mask %08x shift %d bits %d\n", i, masks.masks[i], masks.shifts[i], masks.bits[i]);*/ } - base_offset += 4 * 4; + /* account for the masks */ + base_offset += 3 * 4; } else { - i_push_errorf(0, "unknown 24-bit BMP compression (%d)", compression); + im_push_errorf(aIMCTX, 0, "unknown 24-bit BMP compression (%d)", compression); return NULL; } if (offbits < base_offset) { - i_push_errorf(0, "image data offset too small (%ld)", offbits); + im_push_errorf(aIMCTX, 0, "image data offset too small (%ld)", offbits); return NULL; } @@ -1330,7 +1425,7 @@ read_direct_bmp(io_glue *ig, int xsize, int ysize, int bit_count, rare */ char buffer; while (base_offset < offbits) { - if (ig->readcb(ig, &buffer, 1) != 1) { + if (i_io_read(ig, &buffer, 1) != 1) { i_push_error(0, "failed skipping to image data offset"); return NULL; } @@ -1356,7 +1451,7 @@ read_direct_bmp(io_glue *ig, int xsize, int ysize, int bit_count, while (y != lasty) { p = line; for (x = 0; x < xsize; ++x) { - unsigned pixel; + i_packed_t pixel; if (!read_packed(ig, unpack_code, &pixel)) { myfree(line); if (allow_incomplete) { @@ -1371,16 +1466,21 @@ read_direct_bmp(io_glue *ig, int xsize, int ysize, int bit_count, } } for (i = 0; i < 3; ++i) { - if (masks.shifts[i] > 0) - p->channel[i] = (pixel & masks.masks[i]) >> masks.shifts[i]; - else - p->channel[i] = (pixel & masks.masks[i]) << -masks.shifts[i]; + int sample = (pixel & masks.masks[i]) >> masks.shifts[i]; + int bits = masks.bits[i]; + if (bits < 8) { + sample = (sample * samp_converts[bits-1].mult) >> samp_converts[bits-1].shift; + } + else if (bits) { + sample >>= bits - 8; + } + p->channel[i] = sample; } ++p; } i_plin(im, 0, xsize, y, line); if (extras) - ig->readcb(ig, junk, extras); + i_io_read(ig, junk, extras); y += yinc; } myfree(line);