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-rw-r--r--media/libjpeg/jcicc.c105
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diff --git a/media/libjpeg/jcicc.c b/media/libjpeg/jcicc.c
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+/*
+ * jcicc.c
+ *
+ * Copyright (C) 1997-1998, Thomas G. Lane, Todd Newman.
+ * Copyright (C) 2017, D. R. Commander.
+ * For conditions of distribution and use, see the accompanying README.ijg
+ * file.
+ *
+ * This file provides code to write International Color Consortium (ICC) device
+ * profiles embedded in JFIF JPEG image files. The ICC has defined a standard
+ * for including such data in JPEG "APP2" markers. The code given here does
+ * not know anything about the internal structure of the ICC profile data; it
+ * just knows how to embed the profile data in a JPEG file while writing it.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "jerror.h"
+
+
+/*
+ * Since an ICC profile can be larger than the maximum size of a JPEG marker
+ * (64K), we need provisions to split it into multiple markers. The format
+ * defined by the ICC specifies one or more APP2 markers containing the
+ * following data:
+ * Identifying string ASCII "ICC_PROFILE\0" (12 bytes)
+ * Marker sequence number 1 for first APP2, 2 for next, etc (1 byte)
+ * Number of markers Total number of APP2's used (1 byte)
+ * Profile data (remainder of APP2 data)
+ * Decoders should use the marker sequence numbers to reassemble the profile,
+ * rather than assuming that the APP2 markers appear in the correct sequence.
+ */
+
+#define ICC_MARKER (JPEG_APP0 + 2) /* JPEG marker code for ICC */
+#define ICC_OVERHEAD_LEN 14 /* size of non-profile data in APP2 */
+#define MAX_BYTES_IN_MARKER 65533 /* maximum data len of a JPEG marker */
+#define MAX_DATA_BYTES_IN_MARKER (MAX_BYTES_IN_MARKER - ICC_OVERHEAD_LEN)
+
+
+/*
+ * This routine writes the given ICC profile data into a JPEG file. It *must*
+ * be called AFTER calling jpeg_start_compress() and BEFORE the first call to
+ * jpeg_write_scanlines(). (This ordering ensures that the APP2 marker(s) will
+ * appear after the SOI and JFIF or Adobe markers, but before all else.)
+ */
+
+GLOBAL(void)
+jpeg_write_icc_profile(j_compress_ptr cinfo, const JOCTET *icc_data_ptr,
+ unsigned int icc_data_len)
+{
+ unsigned int num_markers; /* total number of markers we'll write */
+ int cur_marker = 1; /* per spec, counting starts at 1 */
+ unsigned int length; /* number of bytes to write in this marker */
+
+ if (icc_data_ptr == NULL || icc_data_len == 0)
+ ERREXIT(cinfo, JERR_BUFFER_SIZE);
+ if (cinfo->global_state < CSTATE_SCANNING)
+ ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
+
+ /* Calculate the number of markers we'll need, rounding up of course */
+ num_markers = icc_data_len / MAX_DATA_BYTES_IN_MARKER;
+ if (num_markers * MAX_DATA_BYTES_IN_MARKER != icc_data_len)
+ num_markers++;
+
+ while (icc_data_len > 0) {
+ /* length of profile to put in this marker */
+ length = icc_data_len;
+ if (length > MAX_DATA_BYTES_IN_MARKER)
+ length = MAX_DATA_BYTES_IN_MARKER;
+ icc_data_len -= length;
+
+ /* Write the JPEG marker header (APP2 code and marker length) */
+ jpeg_write_m_header(cinfo, ICC_MARKER,
+ (unsigned int)(length + ICC_OVERHEAD_LEN));
+
+ /* Write the marker identifying string "ICC_PROFILE" (null-terminated). We
+ * code it in this less-than-transparent way so that the code works even if
+ * the local character set is not ASCII.
+ */
+ jpeg_write_m_byte(cinfo, 0x49);
+ jpeg_write_m_byte(cinfo, 0x43);
+ jpeg_write_m_byte(cinfo, 0x43);
+ jpeg_write_m_byte(cinfo, 0x5F);
+ jpeg_write_m_byte(cinfo, 0x50);
+ jpeg_write_m_byte(cinfo, 0x52);
+ jpeg_write_m_byte(cinfo, 0x4F);
+ jpeg_write_m_byte(cinfo, 0x46);
+ jpeg_write_m_byte(cinfo, 0x49);
+ jpeg_write_m_byte(cinfo, 0x4C);
+ jpeg_write_m_byte(cinfo, 0x45);
+ jpeg_write_m_byte(cinfo, 0x0);
+
+ /* Add the sequencing info */
+ jpeg_write_m_byte(cinfo, cur_marker);
+ jpeg_write_m_byte(cinfo, (int)num_markers);
+
+ /* Add the profile data */
+ while (length--) {
+ jpeg_write_m_byte(cinfo, *icc_data_ptr);
+ icc_data_ptr++;
+ }
+ cur_marker++;
+ }
+}