diff options
Diffstat (limited to 'source/blender/imbuf/intern/jpeg.c')
| -rw-r--r-- | source/blender/imbuf/intern/jpeg.c | 117 |
1 files changed, 112 insertions, 5 deletions
diff --git a/source/blender/imbuf/intern/jpeg.c b/source/blender/imbuf/intern/jpeg.c index 6fb1fb52153..cffa61977f7 100644 --- a/source/blender/imbuf/intern/jpeg.c +++ b/source/blender/imbuf/intern/jpeg.c @@ -39,7 +39,11 @@ static void skip_input_data(j_decompress_ptr cinfo, long num_bytes); static void term_source(j_decompress_ptr cinfo); static void memory_source(j_decompress_ptr cinfo, const unsigned char *buffer, size_t size); static boolean handle_app1(j_decompress_ptr cinfo); -static ImBuf *ibJpegImageFromCinfo(struct jpeg_decompress_struct *cinfo, int flags); +static ImBuf *ibJpegImageFromCinfo(struct jpeg_decompress_struct *cinfo, + int flags, + int max_size, + size_t *r_width, + size_t *r_height); static const uchar jpeg_default_quality = 75; static uchar ibuf_quality; @@ -246,7 +250,11 @@ static boolean handle_app1(j_decompress_ptr cinfo) return true; } -static ImBuf *ibJpegImageFromCinfo(struct jpeg_decompress_struct *cinfo, int flags) +static ImBuf *ibJpegImageFromCinfo(struct jpeg_decompress_struct *cinfo, + int flags, + int max_size, + size_t *r_width, + size_t *r_height) { JSAMPARRAY row_pointer; JSAMPLE *buffer = NULL; @@ -264,16 +272,34 @@ static ImBuf *ibJpegImageFromCinfo(struct jpeg_decompress_struct *cinfo, int fla jpeg_save_markers(cinfo, JPEG_COM, 0xffff); if (jpeg_read_header(cinfo, false) == JPEG_HEADER_OK) { - x = cinfo->image_width; - y = cinfo->image_height; depth = cinfo->num_components; if (cinfo->jpeg_color_space == JCS_YCCK) { cinfo->out_color_space = JCS_CMYK; } + if (r_width) { + *r_width = cinfo->image_width; + } + if (r_height) { + *r_height = cinfo->image_height; + } + + if (max_size > 0) { + /* `libjpeg` can more quickly decompress while scaling down to 1/2, 1/4, 1/8, + * while `libjpeg-turbo` can also do 3/8, 5/8, etc. But max is 1/8. */ + float scale = (float)max_size / MAX2(cinfo->image_width, cinfo->image_height); + cinfo->scale_denom = 8; + cinfo->scale_num = max_uu(1, min_uu(8, ceill(scale * (float)cinfo->scale_denom))); + cinfo->dct_method = JDCT_FASTEST; + cinfo->dither_mode = JDITHER_ORDERED; + } + jpeg_start_decompress(cinfo); + x = cinfo->output_width; + y = cinfo->output_height; + if (flags & IB_test) { jpeg_abort_decompress(cinfo); ibuf = IMB_allocImBuf(x, y, 8 * depth, 0); @@ -449,11 +475,92 @@ ImBuf *imb_load_jpeg(const unsigned char *buffer, jpeg_create_decompress(cinfo); memory_source(cinfo, buffer, size); - ibuf = ibJpegImageFromCinfo(cinfo, flags); + ibuf = ibJpegImageFromCinfo(cinfo, flags, -1, NULL, NULL); + + return ibuf; +} + +/* Defines for JPEG Header markers and segment size. */ +#define JPEG_MARKER_MSB (0xFF) +#define JPEG_MARKER_SOI (0xD8) +#define JPEG_MARKER_APP1 (0xE1) +#define JPEG_APP1_MAX (1 << 16) + +struct ImBuf *imb_thumbnail_jpeg(const char *filepath, + const int flags, + const size_t max_thumb_size, + char colorspace[IM_MAX_SPACE], + size_t *r_width, + size_t *r_height) +{ + struct jpeg_decompress_struct _cinfo, *cinfo = &_cinfo; + struct my_error_mgr jerr; + FILE *infile = NULL; + + colorspace_set_default_role(colorspace, IM_MAX_SPACE, COLOR_ROLE_DEFAULT_BYTE); + + cinfo->err = jpeg_std_error(&jerr.pub); + jerr.pub.error_exit = jpeg_error; + + /* Establish the setjmp return context for my_error_exit to use. */ + if (setjmp(jerr.setjmp_buffer)) { + /* If we get here, the JPEG code has signaled an error. + * We need to clean up the JPEG object, close the input file, and return. + */ + jpeg_destroy_decompress(cinfo); + return NULL; + } + + if ((infile = BLI_fopen(filepath, "rb")) == NULL) { + fprintf(stderr, "can't open %s\n", filepath); + return NULL; + } + + /* If file contains an embedded thumbnail, let's return that instead. */ + + if ((fgetc(infile) == JPEG_MARKER_MSB) && (fgetc(infile) == JPEG_MARKER_SOI) && + (fgetc(infile) == JPEG_MARKER_MSB) && (fgetc(infile) == JPEG_MARKER_APP1)) { + /* This is a JPEG in EXIF format (SOI + APP1), not JFIF (SOI + APP0). */ + unsigned int i = JPEG_APP1_MAX; + /* All EXIF data is within this 64K header segment. Skip ahead until next SOI for thumbnail. */ + while (!((fgetc(infile) == JPEG_MARKER_MSB) && (fgetc(infile) == JPEG_MARKER_SOI)) && + !feof(infile) && i--) + ; + if (i > 0 && !feof(infile)) { + /* We found a JPEG thumbnail inside this image. */ + ImBuf *ibuf = NULL; + uchar *buffer = MEM_callocN(JPEG_APP1_MAX, "thumbbuffer"); + /* Just put SOI directly in buffer rather than seeking back 2 bytes. */ + buffer[0] = JPEG_MARKER_MSB; + buffer[1] = JPEG_MARKER_SOI; + if (fread(buffer + 2, JPEG_APP1_MAX - 2, 1, infile) == 1) { + ibuf = imb_load_jpeg(buffer, JPEG_APP1_MAX, flags, colorspace); + } + MEM_SAFE_FREE(buffer); + if (ibuf) { + fclose(infile); + return ibuf; + } + } + } + + /* No embedded thumbnail found, so let's create a new one. */ + + fseek(infile, 0, SEEK_SET); + jpeg_create_decompress(cinfo); + + jpeg_stdio_src(cinfo, infile); + ImBuf *ibuf = ibJpegImageFromCinfo(cinfo, flags, max_thumb_size, r_width, r_height); + fclose(infile); return ibuf; } +#undef JPEG_MARKER_MSB +#undef JPEG_MARKER_SOI +#undef JPEG_MARKER_APP1 +#undef JPEG_APP1_MAX + static void write_jpeg(struct jpeg_compress_struct *cinfo, struct ImBuf *ibuf) { JSAMPLE *buffer = NULL; |