Decode JBIG and JPEG during HN conversion.

1 files changed, 36 insertions, 0 deletions

diff --git a/src/jpeg.c b/src/jpeg.c
new file mode 100644
index 0000000..4ea4d7f
--- /dev/null
+++ b/src/jpeg.c
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2020-2021, yzrh <yzrh@noema.org>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <stdio.h>
+
+#include <jpeglib.h>
+
+int
+strinfo_jpeg_dim(int *jpeg_width, int *jpeg_height,
+	const char * restrict data, int data_size)
+{
+	struct jpeg_decompress_struct cinfo;
+	struct jpeg_error_mgr jerr;
+
+	cinfo.err = jpeg_std_error(&jerr);
+
+	jpeg_create_decompress(&cinfo);
+
+	jpeg_mem_src(&cinfo, (unsigned char *) data, data_size);
+
+	jpeg_read_header(&cinfo, TRUE);
+
+	jpeg_calc_output_dimensions(&cinfo);
+
+	*jpeg_width = cinfo.output_width;
+	*jpeg_height = cinfo.output_height;
+
+	jpeg_destroy((struct jpeg_common_struct *) &cinfo);
+
+	jpeg_destroy_decompress(&cinfo);
+
+	return 0;
+}