diff --git a/stb_image_write.h b/stb_image_write.h index 5a906b5..0deaf3b 100644 --- a/stb_image_write.h +++ b/stb_image_write.h @@ -17,7 +17,7 @@ ABOUT: The PNG output is not optimal; it is 20-50% larger than the file written by a decent optimizing implementation. This library is designed - for source code compactness and simplicitly, not optimal image file size + for source code compactness and simplicity, not optimal image file size or run-time performance. BUILDING: @@ -36,6 +36,18 @@ USAGE: int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data); int stbi_write_hdr(char const *filename, int w, int h, int comp, const void *data); + There are also four equivalent functions that use an arbitrary write function. You are + expected to open/close your file-equivalent before and after calling these: + + int stbi_write_png_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data, int stride_in_bytes); + int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); + int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); + int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data); + + You can define STBI_WRITE_NO_STDIO to disable the file variant of these + functions, so the library will not use stdio.h at all. However, this will + also disable HDR writing, because it requires stdio for formatted output. + Each function returns 0 on failure and non-0 on success. The functions create an image file defined by the parameters. The image @@ -77,6 +89,8 @@ CREDITS: Tim Kelsey TGA RLE Alan Hickman + file IO callback + Emmanuel Julien bugfixes: github:Chribba Guillaume Chereau @@ -87,6 +101,7 @@ LICENSE This software is in the public domain. Where that dedication is not recognized, you are granted a perpetual, irrevocable license to copy, distribute, and modify this file as you see fit. + */ #ifndef INCLUDE_STB_IMAGE_WRITE_H @@ -103,10 +118,19 @@ extern "C" { extern int stbi_write_tga_with_rle; #endif +#ifndef STBI_WRITE_NO_STDIO STBIWDEF int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes); STBIWDEF int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data); STBIWDEF int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data); STBIWDEF int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data); +#endif + +typedef int stbi_write_func(void *context, void *data, int size); + +STBIWDEF int stbi_write_png_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data, int stride_in_bytes); +STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); +STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); +STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data); #ifdef __cplusplus } @@ -121,9 +145,12 @@ STBIWDEF int stbi_write_hdr(char const *filename, int w, int h, int comp, const #define _CRT_NONSTDC_NO_DEPRECATE #endif +#ifndef STBI_WRITE_NO_STDIO +#include +#endif // STBI_WRITE_NO_STDIO + #include #include -#include #include #include @@ -150,29 +177,70 @@ STBIWDEF int stbi_write_hdr(char const *filename, int w, int h, int comp, const #define STBIW_ASSERT(x) assert(x) #endif +typedef struct +{ + stbi_write_func *func; + void *context; +} stbi__write_context; + +// initialize a callback-based context +static void stbi__start_write_callbacks(stbi__write_context *s, stbi_write_func *c, void *context) +{ + s->func = c; + s->context = context; +} + +#ifndef STBI_WRITE_NO_STDIO + +static int stbi__stdio_write(void *user, void *data, int size) +{ + return (int) fwrite(data,1,size,(FILE*) user); +} + +static void stbi__start_write_file(stbi__write_context *s, const char *filename) +{ + FILE *f = fopen(filename, "wb"); + stbi__start_write_callbacks(s, &stbi__stdio_write, (void *) f); +} + +static void stbi__end_write_file(stbi__write_context *s) +{ + fclose((FILE *)s->context); +} + +#endif // !STBI_WRITE_NO_STDIO + typedef unsigned int stbiw_uint32; typedef int stb_image_write_test[sizeof(stbiw_uint32)==4 ? 1 : -1]; - #ifdef STB_IMAGE_WRITE_STATIC static int stbi_write_tga_with_rle = 1; #else int stbi_write_tga_with_rle = 1; #endif -static void writefv(FILE *f, const char *fmt, va_list v) +static void writefv(stbi__write_context *s, const char *fmt, va_list v) { while (*fmt) { switch (*fmt++) { case ' ': break; - case '1': { unsigned char x = (unsigned char) va_arg(v, int); fputc(x,f); break; } - case '2': { int x = va_arg(v,int); unsigned char b[2]; - b[0] = (unsigned char) x; b[1] = (unsigned char) (x>>8); - fwrite(b,2,1,f); break; } - case '4': { stbiw_uint32 x = va_arg(v,int); unsigned char b[4]; - b[0]=(unsigned char)x; b[1]=(unsigned char)(x>>8); - b[2]=(unsigned char)(x>>16); b[3]=(unsigned char)(x>>24); - fwrite(b,4,1,f); break; } + case '1': { unsigned char x = (unsigned char) va_arg(v, int); + s->func(s->context,&x,1); + break; } + case '2': { int x = va_arg(v,int); + unsigned char b[2]; + b[0] = (unsigned char) x; + b[1] = (unsigned char) (x>>8); + s->func(s->context,b,2); + break; } + case '4': { stbiw_uint32 x = va_arg(v,int); + unsigned char b[4]; + b[0]=(unsigned char)x; + b[1]=(unsigned char)(x>>8); + b[2]=(unsigned char)(x>>16); + b[3]=(unsigned char)(x>>24); + s->func(s->context,b,4); + break; } default: STBIW_ASSERT(0); return; @@ -180,54 +248,57 @@ static void writefv(FILE *f, const char *fmt, va_list v) } } -static void writef(FILE *f, const char *fmt, ...) +static void writef(stbi__write_context *s, const char *fmt, ...) { va_list v; va_start(v, fmt); - writefv(f, fmt, v); + writefv(s, fmt, v); va_end(v); } -static void write3(FILE *f, unsigned char a, unsigned char b, unsigned char c) +static void write3(stbi__write_context *s, unsigned char a, unsigned char b, unsigned char c) { unsigned char arr[3]; arr[0] = a, arr[1] = b, arr[2] = c; - fwrite(arr, 3, 1, f); + s->func(s->context, arr, 3); } -static void write_pixel(FILE *f, int rgb_dir, int comp, int write_alpha, int expand_mono, const unsigned char *d) +static void write_pixel(stbi__write_context *s, int rgb_dir, int comp, int write_alpha, int expand_mono, unsigned char *d) { unsigned char bg[3] = { 255, 0, 255}, px[3]; int k; if (write_alpha < 0) - fwrite(&d[comp - 1], 1, 1, f); + s->func(s->context, &d[comp - 1], 1); + switch (comp) { - case 1: fwrite(d, 1, 1, f); - break; - case 2: if (expand_mono) - write3(f, d[0], d[0], d[0]); // monochrome bmp - else - fwrite(d, 1, 1, f); // monochrome TGA - break; - case 4: - if (!write_alpha) { - // composite against pink background - for (k = 0; k < 3; ++k) - px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255; - write3(f, px[1 - rgb_dir], px[1], px[1 + rgb_dir]); + case 1: + s->func(s->context,d,1); + break; + case 2: + if (expand_mono) + write3(s, d[0], d[0], d[0]); // monochrome bmp + else + s->func(s->context, d, 1); // monochrome TGA + break; + case 4: + if (!write_alpha) { + // composite against pink background + for (k = 0; k < 3; ++k) + px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255; + write3(s, px[1 - rgb_dir], px[1], px[1 + rgb_dir]); + break; + } + /* FALLTHROUGH */ + case 3: + write3(s, d[1 - rgb_dir], d[1], d[1 + rgb_dir]); break; - } - /* FALLTHROUGH */ - case 3: - write3(f, d[1 - rgb_dir], d[1], d[1 + rgb_dir]); - break; } if (write_alpha > 0) - fwrite(&d[comp - 1], 1, 1, f); + s->func(s->context, &d[comp - 1], 1); } -static void write_pixels(FILE *f, int rgb_dir, int vdir, int x, int y, int comp, void *data, int write_alpha, int scanline_pad, int expand_mono) +static void write_pixels(stbi__write_context *s, int rgb_dir, int vdir, int x, int y, int comp, void *data, int write_alpha, int scanline_pad, int expand_mono) { stbiw_uint32 zero = 0; int i,j, j_end; @@ -243,62 +314,77 @@ static void write_pixels(FILE *f, int rgb_dir, int vdir, int x, int y, int comp, for (; j != j_end; j += vdir) { for (i=0; i < x; ++i) { unsigned char *d = (unsigned char *) data + (j*x+i)*comp; - write_pixel(f, rgb_dir, comp, write_alpha, expand_mono, d); + write_pixel(s, rgb_dir, comp, write_alpha, expand_mono, d); } - fwrite(&zero,scanline_pad,1,f); + s->func(s->context, &zero, scanline_pad); } } -static int outfile(char const *filename, int rgb_dir, int vdir, int x, int y, int comp, int expand_mono, void *data, int alpha, int pad, const char *fmt, ...) +static int outfile(stbi__write_context *s, int rgb_dir, int vdir, int x, int y, int comp, int expand_mono, void *data, int alpha, int pad, const char *fmt, ...) { - FILE *f; - if (y < 0 || x < 0) return 0; - f = fopen(filename, "wb"); - if (f) { + if (y < 0 || x < 0) { + return 0; + } else { va_list v; va_start(v, fmt); - writefv(f, fmt, v); + writefv(s, fmt, v); va_end(v); - write_pixels(f,rgb_dir,vdir,x,y,comp,data,alpha,pad,expand_mono); - fclose(f); + write_pixels(s,rgb_dir,vdir,x,y,comp,data,alpha,pad, expand_mono); + return 1; } - return f != NULL; } -STBIWDEF int stbi_write_bmp(char const *filename, int x, int y, int comp, const void *data) +STBIWDEF int stbi_write_bmp_core(stbi__write_context *s, int x, int y, int comp, const void *data) { int pad = (-x*3) & 3; - return outfile(filename,-1,-1,x,y,comp,1,(void *) data,0,pad, + return outfile(s,-1,-1,x,y,comp,1,(void *) data,0,pad, "11 4 22 4" "4 44 22 444444", 'B', 'M', 14+40+(x*3+pad)*y, 0,0, 14+40, // file header 40, x,y, 1,24, 0,0,0,0,0,0); // bitmap header } -STBIWDEF int stbi_write_tga(char const *filename, int x, int y, int comp, const void *data) +STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data) +{ + stbi__write_context s; + stbi__start_write_callbacks(&s, func, context); + return stbi_write_bmp_core(&s, x, y, comp, data); +} + +#ifndef STBI_WRITE_NO_STDIO +STBIWDEF int stbi_write_bmp(char const *filename, int x, int y, int comp, const void *data) +{ + int r; + stbi__write_context s; + stbi__start_write_file(&s,filename); + r = stbi_write_bmp_core(&s, x, y, comp, data); + stbi__end_write_file(&s); + return r; +} +#endif //!STBI_WRITE_NO_STDIO + +STBIWDEF int stbi_write_tga_core(stbi__write_context *s, int x, int y, int comp, void *data) { int has_alpha = (comp == 2 || comp == 4); int colorbytes = has_alpha ? comp-1 : comp; int format = colorbytes < 2 ? 3 : 2; // 3 color channels (RGB/RGBA) = 2, 1 color channel (Y/YA) = 3 - FILE *f; + + if (y < 0 || x < 0) + return 0; if (!stbi_write_tga_with_rle) { - return outfile(filename, -1, -1, x, y, comp, 0, (void *) data, has_alpha, 0, + return outfile(s, -1, -1, x, y, comp, 0, (void *) data, has_alpha, 0, "111 221 2222 11", 0, 0, format, 0, 0, 0, 0, 0, x, y, (colorbytes + has_alpha) * 8, has_alpha * 8); - } - - if (y < 0 || x < 0) return 0; - f = fopen(filename, "wb"); - if (f) { + } else { int i,j,k; - writef(f, "111 221 2222 11", 0,0,format+8, 0,0,0, 0,0,x,y, (colorbytes + has_alpha) * 8, has_alpha * 8); + writef(s, "111 221 2222 11", 0,0,format+8, 0,0,0, 0,0,x,y, (colorbytes + has_alpha) * 8, has_alpha * 8); for (j = y - 1; j >= 0; --j) { - const unsigned char *row = (unsigned char *) data + j * x * comp; + unsigned char *row = (unsigned char *) data + j * x * comp; int len; for (i = 0; i < x; i += len) { - const unsigned char *begin = row + i * comp; + unsigned char *begin = row + i * comp; int diff = 1; len = 1; @@ -329,27 +415,45 @@ STBIWDEF int stbi_write_tga(char const *filename, int x, int y, int comp, const if (diff) { unsigned char header = (unsigned char) (len - 1); - fwrite(&header, 1, 1, f); + s->func(s->context, &header, 1); for (k = 0; k < len; ++k) { - write_pixel(f, -1, comp, has_alpha, 0, begin + k * comp); + write_pixel(s, -1, comp, has_alpha, 0, begin + k * comp); } } else { unsigned char header = (unsigned char) (len - 129); - fwrite(&header, 1, 1, f); - write_pixel(f, -1, comp, has_alpha, 0, begin); + s->func(s->context, &header, 1); + write_pixel(s, -1, comp, has_alpha, 0, begin); } } } - - fclose(f); } - - return f != NULL; + return 1; } +int stbi_write_tga_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data) +{ + stbi__write_context s; + stbi__start_write_callbacks(&s, func, context); + return stbi_write_tga_core(&s, x, y, comp, (void *) data); +} + +#ifndef STBI_WRITE_NO_STDIO +int stbi_write_tga_to_file(char const *filename, int x, int y, int comp, const void *data) +{ + int r; + stbi__write_context s; + stbi__start_write_file(&s,filename); + r = stbi_write_tga_core(&s, x, y, comp, (void *) data); + stbi__end_write_file(&s); + return r; +} +#endif + // ************************************************************************************************* // Radiance RGBE HDR writer // by Baldur Karlsson +#ifndef STBI_WRITE_NO_STDIO + #define stbiw__max(a, b) ((a) > (b) ? (a) : (b)) void stbiw__linear_to_rgbe(unsigned char *rgbe, float *linear) @@ -369,23 +473,23 @@ void stbiw__linear_to_rgbe(unsigned char *rgbe, float *linear) } } -void stbiw__write_run_data(FILE *f, int length, unsigned char databyte) +void stbiw__write_run_data(stbi__write_context *s, int length, unsigned char databyte) { unsigned char lengthbyte = (unsigned char) (length+128); STBIW_ASSERT(length+128 <= 255); - fwrite(&lengthbyte, 1, 1, f); - fwrite(&databyte, 1, 1, f); + s->func(s->context, &lengthbyte, 1); + s->func(s->context, &databyte, 1); } -void stbiw__write_dump_data(FILE *f, int length, unsigned char *data) +void stbiw__write_dump_data(stbi__write_context *s, int length, unsigned char *data) { unsigned char lengthbyte = (unsigned char )(length & 0xff); STBIW_ASSERT(length <= 128); // inconsistent with spec but consistent with official code - fwrite(&lengthbyte, 1, 1, f); - fwrite(data, length, 1, f); + s->func(s->context, &lengthbyte, 1); + s->func(s->context, data, length); } -void stbiw__write_hdr_scanline(FILE *f, int width, int ncomp, unsigned char *scratch, const float *scanline) +void stbiw__write_hdr_scanline(stbi__write_context *s, int width, int ncomp, unsigned char *scratch, float *scanline) { unsigned char scanlineheader[4] = { 2, 2, 0, 0 }; unsigned char rgbe[4]; @@ -409,7 +513,7 @@ void stbiw__write_hdr_scanline(FILE *f, int width, int ncomp, unsigned char *scr break; } stbiw__linear_to_rgbe(rgbe, linear); - fwrite(rgbe, 4, 1, f); + s->func(s->context, rgbe, 4); } } else { int c,r; @@ -432,7 +536,7 @@ void stbiw__write_hdr_scanline(FILE *f, int width, int ncomp, unsigned char *scr scratch[x + width*3] = rgbe[3]; } - fwrite(scanlineheader, 4, 1, f); + s->func(s->context, scanlineheader, 4); /* RLE each component separately */ for (c=0; c < 4; c++) { @@ -453,7 +557,7 @@ void stbiw__write_hdr_scanline(FILE *f, int width, int ncomp, unsigned char *scr while (x < r) { int len = r-x; if (len > 128) len = 128; - stbiw__write_dump_data(f, len, &comp[x]); + stbiw__write_dump_data(s, len, &comp[x]); x += len; } // if there's a run, output it @@ -465,7 +569,7 @@ void stbiw__write_hdr_scanline(FILE *f, int width, int ncomp, unsigned char *scr while (x < r) { int len = r-x; if (len > 127) len = 127; - stbiw__write_run_data(f, len, comp[x]); + stbiw__write_run_data(s, len, comp[x]); x += len; } } @@ -474,27 +578,51 @@ void stbiw__write_hdr_scanline(FILE *f, int width, int ncomp, unsigned char *scr } } -STBIWDEF int stbi_write_hdr(char const *filename, int x, int y, int comp, const float *data) +STBIWDEF int stbi_write_hdr_core(stbi__write_context *s, int x, int y, int comp, float *data) { - int i; - FILE *f; - if (y <= 0 || x <= 0 || data == NULL) return 0; - f = fopen(filename, "wb"); - if (f) { - /* Each component is stored separately. Allocate scratch space for full output scanline. */ + if (y <= 0 || x <= 0 || data == NULL) + return 0; + else { + // Each component is stored separately. Allocate scratch space for full output scanline. unsigned char *scratch = (unsigned char *) STBIW_MALLOC(x*4); - fprintf(f, "#?RADIANCE\n# Written by stb_image_write.h\nFORMAT=32-bit_rle_rgbe\n" ); - fprintf(f, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n" , y, x); + int i, len; + char buffer[128]; + char header[] = "#?RADIANCE\n# Written by stb_image_write.h\nFORMAT=32-bit_rle_rgbe\n"; + s->func(s->context, header, sizeof(header)-1); + + len = sprintf(buffer, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", y, x); + s->func(s->context, buffer, len); + for(i=0; i < y; i++) - stbiw__write_hdr_scanline(f, x, comp, scratch, data + comp*i*x); + stbiw__write_hdr_scanline(s, x, comp, scratch, data + comp*i*x); STBIW_FREE(scratch); - fclose(f); + return 1; } - return f != NULL; } -///////////////////////////////////////////////////////// -// PNG +int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const float *data) +{ + stbi__write_context s; + stbi__start_write_callbacks(&s, func, context); + return stbi_write_hdr_core(&s, x, y, comp, (float *) data); +} + +int stbi_write_hdr_to_file(char const *filename, int x, int y, int comp, const float *data) +{ + int r; + stbi__write_context s; + stbi__start_write_file(&s,filename); + r = stbi_write_hdr_core(&s, x, y, comp, (float *) data); + stbi__end_write_file(&s); + return r; +} +#endif // STBI_WRITE_NO_STDIO + + +////////////////////////////////////////////////////////////////////////////// +// +// PNG writer +// // stretchy buffer; stbiw__sbpush() == vector<>::push_back() -- stbiw__sbcount() == vector<>::size() #define stbiw__sbraw(a) ((int *) (a) - 2) @@ -804,12 +932,13 @@ unsigned char *stbi_write_png_to_mem(unsigned char *pixels, int stride_bytes, in return out; } +#ifndef STBI_WRITE_NO_STDIO STBIWDEF int stbi_write_png(char const *filename, int x, int y, int comp, const void *data, int stride_bytes) { FILE *f; int len; unsigned char *png = stbi_write_png_to_mem((unsigned char *) data, stride_bytes, x, y, comp, &len); - if (!png) return 0; + if (png == NULL) return 0; f = fopen(filename, "wb"); if (!f) { STBIW_FREE(png); return 0; } fwrite(png, 1, len, f); @@ -817,6 +946,18 @@ STBIWDEF int stbi_write_png(char const *filename, int x, int y, int comp, const STBIW_FREE(png); return 1; } +#endif + +STBIWDEF int stbi_write_png_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int stride_bytes) +{ + int len; + unsigned char *png = stbi_write_png_to_mem((unsigned char *) data, stride_bytes, x, y, comp, &len); + if (png == NULL) return 0; + func(context, png, len); + STBIW_FREE(png); + return 1; +} + #endif // STB_IMAGE_WRITE_IMPLEMENTATION /* Revision history