Add a tool to extract LibRaw file information

1 files changed, 155 insertions, 0 deletions

diff --git a/tools/rawinfo.c b/tools/rawinfo.c
new file mode 100644
index 0000000..fa36bba
--- /dev/null
+++ b/tools/rawinfo.c
@@ -0,0 +1,155 @@
+//
+// rawinfo.c: acquire information about raw image files in JSON format
+//
+// Copyright (c) 2023, Přemysl Eric Janouch <p@janouch.name>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+//
+
+#include "info.h"
+
+#include <jv.h>
+#include <libraw.h>
+
+#if LIBRAW_VERSION < LIBRAW_MAKE_VERSION(0, 21, 0)
+#error LibRaw 0.21.0 or newer is required.
+#endif
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+// --- Raw image files ---------------------------------------------------------
+// This is in principle similar to LibRaw's `raw-identify -v`,
+// but the output is machine-processable.
+
+static jv
+parse_raw(jv o, const uint8_t *p, size_t len)
+{
+	libraw_data_t *iprc = libraw_init(LIBRAW_OPIONS_NO_DATAERR_CALLBACK);
+	if (!iprc)
+		return add_error(o, "failed to obtain a LibRaw handle");
+
+	int err = 0;
+	if ((err = libraw_open_buffer(iprc, p, len))) {
+		libraw_close(iprc);
+		return add_error(o, libraw_strerror(err));
+	}
+
+	o = jv_set(o, jv_string("width"), jv_number(iprc->sizes.width));
+	o = jv_set(o, jv_string("height"), jv_number(iprc->sizes.height));
+	o = jv_set(o, jv_string("flip"), jv_number(iprc->sizes.flip));
+
+	// -> iprc->rawparams.shot_select
+	o = jv_set(o, jv_string("count"), jv_number(iprc->idata.raw_count));
+
+	jv thumbnails = jv_array();
+	for (int i = 0; i < iprc->thumbs_list.thumbcount; i++) {
+		libraw_thumbnail_item_t *item = iprc->thumbs_list.thumblist + i;
+
+		const char *format = "?";
+		switch (item->tformat) {
+		case LIBRAW_INTERNAL_THUMBNAIL_UNKNOWN:
+			format = "unknown";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_KODAK_THUMB:
+			format = "Kodak thumbnail";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_KODAK_YCBCR:
+			format = "Kodak YCbCr";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_KODAK_RGB:
+			format = "Kodak RGB";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_JPEG:
+			format = "JPEG";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_LAYER:
+			format = "layer";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_ROLLEI:
+			format = "Rollei";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_PPM:
+			format = "PPM";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_PPM16:
+			format = "PPM16";
+			break;
+		case LIBRAW_INTERNAL_THUMBNAIL_X3F:
+			format = "X3F";
+			break;
+		}
+
+		thumbnails = jv_array_append(thumbnails,
+			JV_OBJECT(jv_string("width"), jv_number(item->twidth),
+				jv_string("height"), jv_number(item->theight),
+				jv_string("flip"), jv_number(item->tflip),
+				jv_string("format"), jv_string(format)));
+	}
+
+	libraw_close(iprc);
+	return jv_set(o, jv_string("thumbnails"), thumbnails);
+}
+
+// --- I/O ---------------------------------------------------------------------
+
+static jv
+do_file(const char *filename, jv o)
+{
+	const char *err = NULL;
+	FILE *fp = fopen(filename, "rb");
+	if (!fp) {
+		err = strerror(errno);
+		goto error;
+	}
+
+	uint8_t *data = NULL, buf[256 << 10];
+	size_t n, len = 0;
+	while ((n = fread(buf, sizeof *buf, sizeof buf / sizeof *buf, fp))) {
+		data = realloc(data, len + n);
+		memcpy(data + len, buf, n);
+		len += n;
+	}
+	if (ferror(fp)) {
+		err = strerror(errno);
+		goto error_read;
+	}
+
+	o = parse_raw(o, data, len);
+
+error_read:
+	fclose(fp);
+	free(data);
+error:
+	if (err)
+		o = add_error(o, err);
+	return o;
+}
+
+int
+main(int argc, char *argv[])
+{
+	// XXX: Can't use `xargs -P0`, there's a risk of non-atomic writes.
+	// Usage: find . -iname *.png -print0 | xargs -0 ./rawinfo
+	for (int i = 1; i < argc; i++) {
+		const char *filename = argv[i];
+
+		jv o = jv_object();
+		o = jv_object_set(o, jv_string("filename"), jv_string(filename));
+		o = do_file(filename, o);
+		jv_dumpf(o, stdout, 0 /* Might consider JV_PRINT_SORTED. */);
+		fputc('\n', stdout);
+	}
+	return 0;
+}