1 files changed, 226 insertions, 0 deletions
diff --git a/backend/epsonds-jpeg.c b/backend/epsonds-jpeg.c
new file mode 100644
index 0000000..76a52cb
--- /dev/null
+++ b/backend/epsonds-jpeg.c
@@ -0,0 +1,226 @@
+/*
+ * epsonds-jpeg.c - Epson ESC/I-2 driver, JPEG support.
+ *
+ * Copyright (C) 2015 Tower Technologies
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
+ *
+ * This file is part of the SANE package.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2.
+ */
+
+#define DEBUG_DECLARE_ONLY
+
+#include <math.h>
+
+#include "epsonds.h"
+#include "epsonds-jpeg.h"
+#include "epsonds-ops.h"
+
+#define min(A,B) (((A)<(B)) ? (A) : (B))
+
+typedef struct
+{
+	struct jpeg_source_mgr pub;
+
+	epsonds_scanner *s;
+	JOCTET *buffer;
+
+	SANE_Byte *linebuffer;
+	SANE_Int linebuffer_size;
+	SANE_Int linebuffer_index;
+}
+epsonds_src_mgr;
+
+METHODDEF(void)
+jpeg_init_source(j_decompress_ptr UNUSEDARG cinfo)
+{
+}
+
+METHODDEF(void)
+jpeg_term_source(j_decompress_ptr UNUSEDARG cinfo)
+{
+}
+
+METHODDEF(boolean)
+jpeg_fill_input_buffer(j_decompress_ptr cinfo)
+{
+	epsonds_src_mgr *src = (epsonds_src_mgr *)cinfo->src;
+	int avail, size;
+
+	/* read from the scanner or the ring buffer */
+
+	avail = eds_ring_avail(src->s->current);
+	if (avail == 0) {
+		return FALSE;
+	}
+
+	/* read from scanner if no data? */
+	size = min(1024, avail);
+
+	eds_ring_read(src->s->current, src->buffer, size);
+
+	src->pub.next_input_byte = src->buffer;
+	src->pub.bytes_in_buffer = size;
+
+	return TRUE;
+}
+
+METHODDEF (void)
+jpeg_skip_input_data(j_decompress_ptr cinfo, long num_bytes)
+{
+	epsonds_src_mgr *src = (epsonds_src_mgr *)cinfo->src;
+
+	if (num_bytes > 0) {
+
+		while (num_bytes > (long)src->pub.bytes_in_buffer) {
+			num_bytes -= (long)src->pub.bytes_in_buffer;
+			jpeg_fill_input_buffer(cinfo);
+		}
+
+		src->pub.next_input_byte += (size_t) num_bytes;
+		src->pub.bytes_in_buffer -= (size_t) num_bytes;
+	}
+}
+
+SANE_Status
+eds_jpeg_start(epsonds_scanner *s)
+{
+	epsonds_src_mgr *src;
+
+	s->jpeg_cinfo.err = jpeg_std_error(&s->jpeg_err);
+
+	jpeg_create_decompress(&s->jpeg_cinfo);
+
+	s->jpeg_cinfo.src = (struct jpeg_source_mgr *)(*s->jpeg_cinfo.mem->alloc_small)((j_common_ptr)&s->jpeg_cinfo,
+						JPOOL_PERMANENT, sizeof(epsonds_src_mgr));
+
+	memset(s->jpeg_cinfo.src, 0x00, sizeof(epsonds_src_mgr));
+
+	src = (epsonds_src_mgr *)s->jpeg_cinfo.src;
+	src->s = s;
+
+	src->buffer = (JOCTET *)(*s->jpeg_cinfo.mem->alloc_small)((j_common_ptr)&s->jpeg_cinfo,
+							JPOOL_PERMANENT,
+							1024 * sizeof(JOCTET));
+
+	src->pub.init_source = jpeg_init_source;
+	src->pub.fill_input_buffer = jpeg_fill_input_buffer;
+	src->pub.skip_input_data = jpeg_skip_input_data;
+	src->pub.resync_to_restart = jpeg_resync_to_restart;
+	src->pub.term_source = jpeg_term_source;
+	src->pub.bytes_in_buffer = 0;
+	src->pub.next_input_byte = NULL;
+
+	s->jpeg_header_seen = 0;
+
+	return SANE_STATUS_GOOD;
+}
+
+SANE_Status
+eds_jpeg_read_header(epsonds_scanner *s)
+{
+	epsonds_src_mgr *src = (epsonds_src_mgr *)s->jpeg_cinfo.src;
+
+	if (jpeg_read_header(&s->jpeg_cinfo, TRUE)) {
+
+		s->jdst = sanei_jpeg_jinit_write_ppm(&s->jpeg_cinfo);
+
+		if (jpeg_start_decompress(&s->jpeg_cinfo)) {
+
+			int size;
+
+			DBG(3, "%s: w: %d, h: %d, components: %d\n",
+				__func__,
+				s->jpeg_cinfo.output_width, s->jpeg_cinfo.output_height,
+				s->jpeg_cinfo.output_components);
+
+			size = s->jpeg_cinfo.output_width * s->jpeg_cinfo.output_components * 1;
+
+			src->linebuffer = (*s->jpeg_cinfo.mem->alloc_large)((j_common_ptr)&s->jpeg_cinfo,
+				JPOOL_PERMANENT, size);
+
+			src->linebuffer_size = 0;
+			src->linebuffer_index = 0;
+
+			s->jpeg_header_seen = 1;
+
+			return SANE_STATUS_GOOD;
+
+		} else {
+			DBG(0, "%s: decompression failed\n", __func__);
+			return SANE_STATUS_IO_ERROR;
+		}
+	} else {
+		DBG(0, "%s: cannot read JPEG header\n", __func__);
+		return SANE_STATUS_IO_ERROR;
+	}
+}
+
+void
+eds_jpeg_finish(epsonds_scanner *s)
+{
+	jpeg_destroy_decompress(&s->jpeg_cinfo);
+}
+
+void
+eds_jpeg_read(SANE_Handle handle, SANE_Byte *data,
+	   SANE_Int max_length, SANE_Int *length)
+{
+	epsonds_scanner *s = handle;
+
+	struct jpeg_decompress_struct cinfo = s->jpeg_cinfo;
+	epsonds_src_mgr *src = (epsonds_src_mgr *)s->jpeg_cinfo.src;
+
+	int l;
+
+	*length = 0;
+
+	/* copy from line buffer if available */
+	if (src->linebuffer_size && src->linebuffer_index < src->linebuffer_size) {
+
+		*length = src->linebuffer_size - src->linebuffer_index;
+
+		if (*length > max_length)
+			*length = max_length;
+
+		memcpy(data, src->linebuffer + src->linebuffer_index, *length);
+		src->linebuffer_index += *length;
+
+		return;
+	}
+
+	if (cinfo.output_scanline >= cinfo.output_height) {
+		*length = 0;
+		return;
+	}
+
+	/* scanlines of decompressed data will be in s->jdst->buffer
+	 * only one line at time is supported
+	 */
+
+	l = jpeg_read_scanlines(&cinfo, s->jdst->buffer, 1);
+	if (l == 0) {
+		return;
+	}
+
+	/* from s->jdst->buffer to linebuffer
+	 * linebuffer holds width * bytesperpixel
+	 */
+
+	(*s->jdst->put_pixel_rows)(&cinfo, s->jdst, 1, (char *)src->linebuffer);
+
+	*length = cinfo.output_width * cinfo.output_components * 1;
+	src->linebuffer_size = *length;
+	src->linebuffer_index = 0;
+
+	if (*length > max_length)
+		*length = max_length;
+
+	memcpy(data, src->linebuffer + src->linebuffer_index, *length);
+	src->linebuffer_index += *length;
+}
+
+