Initial revision

1 files changed, 187 insertions, 0 deletions

diff --git a/rd/read-jpeg.c b/rd/read-jpeg.c
new file mode 100644
index 0000000..d12fb40
--- /dev/null
+++ b/rd/read-jpeg.c
@@ -0,0 +1,187 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <errno.h>
+#include <jpeglib.h>
+
+#include <libexif/exif-data.h>
+
+#include "readers.h"
+#include "misc.h"
+
+/* ---------------------------------------------------------------------- */
+/* load                                                                   */
+
+struct jpeg_state {
+    FILE * infile;                /* source file */
+    
+    struct jpeg_decompress_struct cinfo;
+    struct jpeg_error_mgr jerr;
+    JSAMPARRAY buffer;            /* Output row buffer */
+    int row_stride,linelength;    /* physical row width in output buffer */
+    unsigned char *image,*ptr;
+
+    /* thumbnail */
+    unsigned char  *thumbnail;
+    unsigned int   tpos, tsize;
+};
+
+/* ---------------------------------------------------------------------- */
+/* data source manager for thumbnail images                               */
+
+static void thumbnail_src_init(struct jpeg_decompress_struct *cinfo)
+{
+    struct jpeg_state *h  = container_of(cinfo, struct jpeg_state, cinfo);
+    cinfo->src->next_input_byte = h->thumbnail;
+    cinfo->src->bytes_in_buffer = h->tsize;
+}
+
+static int thumbnail_src_fill(struct jpeg_decompress_struct *cinfo)
+{
+    fprintf(stderr,"jpeg: panic: no more thumbnail input data\n");
+    exit(1);
+}
+
+static void thumbnail_src_skip(struct jpeg_decompress_struct *cinfo,
+			       long num_bytes)
+{
+    cinfo->src->next_input_byte += num_bytes;
+}
+
+static void thumbnail_src_term(struct jpeg_decompress_struct *cinfo)
+{
+    /* nothing */
+}
+
+static struct jpeg_source_mgr thumbnail_mgr = {
+    .init_source         = thumbnail_src_init,
+    .fill_input_buffer   = thumbnail_src_fill,
+    .skip_input_data     = thumbnail_src_skip,
+    .resync_to_restart   = jpeg_resync_to_restart,
+    .term_source         = thumbnail_src_term,
+};
+
+/* ---------------------------------------------------------------------- */
+/* jpeg loader                                                            */
+
+static void*
+jpeg_init(FILE *fp, char *filename, unsigned int page,
+	  struct ida_image_info *i, int thumbnail)
+{
+    struct jpeg_state *h;
+    jpeg_saved_marker_ptr mark;
+    
+    h = malloc(sizeof(*h));
+    memset(h,0,sizeof(*h));
+    h->infile = fp;
+
+    h->cinfo.err = jpeg_std_error(&h->jerr);
+    jpeg_create_decompress(&h->cinfo);
+    jpeg_save_markers(&h->cinfo, JPEG_COM,    0xffff); /* comment */
+    jpeg_save_markers(&h->cinfo, JPEG_APP0+1, 0xffff); /* EXIF */
+    jpeg_stdio_src(&h->cinfo, h->infile);
+    jpeg_read_header(&h->cinfo, TRUE);
+
+    for (mark = h->cinfo.marker_list; NULL != mark; mark = mark->next) {
+	switch (mark->marker) {
+	case JPEG_COM:
+	    if (debug)
+		fprintf(stderr,"jpeg: comment found (COM marker) [%.*s]\n",
+			(int)mark->data_length, mark->data);
+	    load_add_extra(i,EXTRA_COMMENT,mark->data,mark->data_length);
+	    break;
+	case JPEG_APP0 +1:
+	    if (debug)
+		fprintf(stderr,"jpeg: exif data found (APP1 marker)\n");
+	    load_add_extra(i,EXTRA_COMMENT,mark->data,mark->data_length);
+
+	    if (thumbnail) {
+		ExifData *ed;
+		
+		ed = exif_data_new_from_data(mark->data,mark->data_length);
+		if (ed->data &&
+		    ed->data[0] == 0xff &&
+		    ed->data[1] == 0xd8) {
+		    if (debug)
+			fprintf(stderr,"jpeg: exif thumbnail found\n");
+
+		    /* save away thumbnail data */
+		    h->thumbnail = malloc(ed->size);
+		    h->tsize = ed->size;
+		    memcpy(h->thumbnail,ed->data,ed->size);
+		}
+		exif_data_unref(ed);
+	    }
+	    break;
+	}
+    }
+
+    if (h->thumbnail) {
+	/* save image size */
+	i->thumbnail   = 1;
+	i->real_width  = h->cinfo.image_width;
+	i->real_height = h->cinfo.image_height;
+
+	/* re-setup jpeg */
+	jpeg_destroy_decompress(&h->cinfo);
+	fclose(h->infile);
+	h->infile = NULL;
+	jpeg_create_decompress(&h->cinfo);
+	h->cinfo.src = &thumbnail_mgr;
+	jpeg_read_header(&h->cinfo, TRUE);
+    }
+
+    h->cinfo.out_color_space = JCS_RGB;
+    jpeg_start_decompress(&h->cinfo);
+    i->width  = h->cinfo.image_width;
+    i->height = h->cinfo.image_height;
+    i->npages = 1;
+    switch (h->cinfo.density_unit) {
+    case 0: /* unknown */
+	break;
+    case 1: /* dot per inch */
+	i->dpi = h->cinfo.X_density;
+	break;
+    case 2: /* dot per cm */
+	i->dpi = res_cm_to_inch(h->cinfo.X_density);
+	break;
+    }
+
+    return h;
+}
+
+static void
+jpeg_read(unsigned char *dst, unsigned int line, void *data)
+{
+    struct jpeg_state *h = data;
+    JSAMPROW row = dst;
+    jpeg_read_scanlines(&h->cinfo, &row, 1);
+}
+
+static void
+jpeg_done(void *data)
+{
+    struct jpeg_state *h = data;
+    jpeg_destroy_decompress(&h->cinfo);
+    if (h->infile)
+	fclose(h->infile);
+    if (h->thumbnail)
+	free(h->thumbnail);
+    free(h);
+}
+
+struct ida_loader jpeg_loader = {
+    magic: "\xff\xd8",
+    moff:  0,
+    mlen:  2,
+    name:  "libjpeg",
+    init:  jpeg_init,
+    read:  jpeg_read,
+    done:  jpeg_done,
+};
+
+static void __init init_rd(void)
+{
+    load_register(&jpeg_loader);
+}