3 * Copyright (C) 2007 David Schleef <ds@schleef.org>
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 * Boston, MA 02111-1307, USA.
21 * Logic enhanced by William Brack <wbrack@mmm.com.hk>
25 * SECTION:element-bayer2rgb
27 * Decodes raw camera bayer (fourcc BA81) to RGB.
31 * In order to guard against my advancing maturity, some extra detailed
32 * information about the logic of the decode is included here. Much of
33 * this was inspired by a technical paper from siliconimaging.com, which
34 * in turn was based upon an article from IEEE,
35 * T. Sakamoto, C. Nakanishi and T. Hase,
36 * “Software pixel interpolation for digital still cameras suitable for
38 * IEEE Trans. Consumer Electronics, vol. 44, no. 4, November 1998.
40 * The code assumes a Bayer matrix of the type produced by the fourcc
41 * BA81 (v4l2 format SBGGR8) of width w and height h which looks like:
51 * We expand this matrix, producing a separate {r, g, b} triple for each
52 * of the individual elements. The algorithm for doing this expansion is
55 * We are designing for speed of transformation, at a slight expense of code.
56 * First, we calculate the appropriate triples for the four corners, the
57 * remainder of the top and bottom rows, and the left and right columns.
58 * The reason for this is that those elements are transformed slightly
59 * differently than all of the remainder of the matrix. Finally, we transform
60 * all of the remainder.
62 * The transformation into the "appropriate triples" is based upon the
63 * "nearest neighbor" principal, with some additional complexity for the
64 * calculation of the "green" element, where an "adaptive" pairing is used.
66 * For purposes of documentation and indentification, each element of the
67 * original array can be put into one of four classes:
70 * GR A green element which is followed by a red one
71 * GB A green element which is followed by a blue one
79 #include <gst/base/gstbasetransform.h>
80 #include <gst/video/video.h>
84 #include "gstbayerorc.h"
86 #define GST_CAT_DEFAULT gst_bayer2rgb_debug
87 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
91 GST_BAYER_2_RGB_FORMAT_BGGR = 0,
92 GST_BAYER_2_RGB_FORMAT_GBRG,
93 GST_BAYER_2_RGB_FORMAT_GRBG,
94 GST_BAYER_2_RGB_FORMAT_RGGB
98 #define GST_TYPE_BAYER2RGB (gst_bayer2rgb_get_type())
99 #define GST_BAYER2RGB(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BAYER2RGB,GstBayer2RGB))
100 #define GST_IS_BAYER2RGB(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BAYER2RGB))
101 #define GST_BAYER2RGB_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass) ,GST_TYPE_BAYER2RGB,GstBayer2RGBClass))
102 #define GST_IS_BAYER2RGB_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass) ,GST_TYPE_BAYER2RGB))
103 #define GST_BAYER2RGB_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS((obj) ,GST_TYPE_BAYER2RGB,GstBayer2RGBClass))
104 typedef struct _GstBayer2RGB GstBayer2RGB;
105 typedef struct _GstBayer2RGBClass GstBayer2RGBClass;
107 typedef void (*GstBayer2RGBProcessFunc) (GstBayer2RGB *, guint8 *, guint);
111 GstBaseTransform basetransform;
117 int pixsize; /* bytes per pixel */
118 int r_off; /* offset for red */
119 int g_off; /* offset for green */
120 int b_off; /* offset for blue */
124 struct _GstBayer2RGBClass
126 GstBaseTransformClass parent;
130 GST_VIDEO_CAPS_RGBx ";" \
131 GST_VIDEO_CAPS_xRGB ";" \
132 GST_VIDEO_CAPS_BGRx ";" \
133 GST_VIDEO_CAPS_xBGR ";" \
134 GST_VIDEO_CAPS_RGBA ";" \
135 GST_VIDEO_CAPS_ARGB ";" \
136 GST_VIDEO_CAPS_BGRA ";" \
139 #define SINK_CAPS "video/x-raw-bayer,format=(string){bggr,grbg,gbrg,rggb}," \
140 "width=(int)[1,MAX],height=(int)[1,MAX],framerate=(fraction)[0/1,MAX]"
147 #define DEBUG_INIT(bla) \
148 GST_DEBUG_CATEGORY_INIT (gst_bayer2rgb_debug, "bayer2rgb", 0, "bayer2rgb element");
150 GType gst_bayer2rgb_get_type (void);
151 GST_BOILERPLATE_FULL (GstBayer2RGB, gst_bayer2rgb, GstBaseTransform,
152 GST_TYPE_BASE_TRANSFORM, DEBUG_INIT);
154 static void gst_bayer2rgb_set_property (GObject * object, guint prop_id,
155 const GValue * value, GParamSpec * pspec);
156 static void gst_bayer2rgb_get_property (GObject * object, guint prop_id,
157 GValue * value, GParamSpec * pspec);
159 static gboolean gst_bayer2rgb_set_caps (GstBaseTransform * filter,
160 GstCaps * incaps, GstCaps * outcaps);
161 static GstFlowReturn gst_bayer2rgb_transform (GstBaseTransform * base,
162 GstBuffer * inbuf, GstBuffer * outbuf);
163 static void gst_bayer2rgb_reset (GstBayer2RGB * filter);
164 static GstCaps *gst_bayer2rgb_transform_caps (GstBaseTransform * base,
165 GstPadDirection direction, GstCaps * caps);
166 static gboolean gst_bayer2rgb_get_unit_size (GstBaseTransform * base,
167 GstCaps * caps, guint * size);
171 gst_bayer2rgb_base_init (gpointer klass)
173 GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
175 gst_element_class_set_details_simple (element_class,
176 "Bayer to RGB decoder for cameras", "Filter/Converter/Video",
177 "Converts video/x-raw-bayer to video/x-raw-rgb",
178 "William Brack <wbrack@mmm.com.hk>");
180 gst_element_class_add_pad_template (element_class,
181 gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
182 gst_caps_from_string (SRC_CAPS)));
183 gst_element_class_add_pad_template (element_class,
184 gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
185 gst_caps_from_string (SINK_CAPS)));
189 gst_bayer2rgb_class_init (GstBayer2RGBClass * klass)
191 GObjectClass *gobject_class;
193 gobject_class = (GObjectClass *) klass;
194 gobject_class->set_property = gst_bayer2rgb_set_property;
195 gobject_class->get_property = gst_bayer2rgb_get_property;
197 GST_BASE_TRANSFORM_CLASS (klass)->transform_caps =
198 GST_DEBUG_FUNCPTR (gst_bayer2rgb_transform_caps);
199 GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size =
200 GST_DEBUG_FUNCPTR (gst_bayer2rgb_get_unit_size);
201 GST_BASE_TRANSFORM_CLASS (klass)->set_caps =
202 GST_DEBUG_FUNCPTR (gst_bayer2rgb_set_caps);
203 GST_BASE_TRANSFORM_CLASS (klass)->transform =
204 GST_DEBUG_FUNCPTR (gst_bayer2rgb_transform);
208 gst_bayer2rgb_init (GstBayer2RGB * filter, GstBayer2RGBClass * klass)
210 gst_bayer2rgb_reset (filter);
211 gst_base_transform_set_in_place (GST_BASE_TRANSFORM (filter), TRUE);
214 /* No properties are implemented, so only a warning is produced */
216 gst_bayer2rgb_set_property (GObject * object, guint prop_id,
217 const GValue * value, GParamSpec * pspec)
222 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
228 gst_bayer2rgb_get_property (GObject * object, guint prop_id,
229 GValue * value, GParamSpec * pspec)
234 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
239 /* Routine to convert colormask value into relative byte offset */
241 get_pix_offset (int mask, int bpp)
243 int bpp32 = (bpp / 8) - 3;
255 GST_ERROR ("Invalid color mask 0x%08x", mask);
261 gst_bayer2rgb_set_caps (GstBaseTransform * base, GstCaps * incaps,
264 GstBayer2RGB *bayer2rgb = GST_BAYER2RGB (base);
265 GstStructure *structure;
269 GST_DEBUG ("in caps %" GST_PTR_FORMAT " out caps %" GST_PTR_FORMAT, incaps,
272 structure = gst_caps_get_structure (incaps, 0);
274 gst_structure_get_int (structure, "width", &bayer2rgb->width);
275 gst_structure_get_int (structure, "height", &bayer2rgb->height);
276 bayer2rgb->stride = GST_ROUND_UP_4 (bayer2rgb->width);
278 format = gst_structure_get_string (structure, "format");
279 if (g_str_equal (format, "bggr")) {
280 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_BGGR;
281 } else if (g_str_equal (format, "gbrg")) {
282 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_GBRG;
283 } else if (g_str_equal (format, "grbg")) {
284 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_GRBG;
285 } else if (g_str_equal (format, "rggb")) {
286 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_RGGB;
291 /* To cater for different RGB formats, we need to set params for later */
292 structure = gst_caps_get_structure (outcaps, 0);
293 gst_structure_get_int (structure, "bpp", &bpp);
294 bayer2rgb->pixsize = bpp / 8;
295 gst_structure_get_int (structure, "red_mask", &val);
296 bayer2rgb->r_off = get_pix_offset (val, bpp);
297 gst_structure_get_int (structure, "green_mask", &val);
298 bayer2rgb->g_off = get_pix_offset (val, bpp);
299 gst_structure_get_int (structure, "blue_mask", &val);
300 bayer2rgb->b_off = get_pix_offset (val, bpp);
306 gst_bayer2rgb_reset (GstBayer2RGB * filter)
318 gst_bayer2rgb_transform_caps (GstBaseTransform * base,
319 GstPadDirection direction, GstCaps * caps)
321 GstStructure *structure;
323 GstStructure *newstruct;
325 GST_DEBUG_OBJECT (caps, "transforming caps (from)");
327 structure = gst_caps_get_structure (caps, 0);
329 if (direction == GST_PAD_SRC) {
330 newcaps = gst_caps_from_string ("video/x-raw-bayer,"
331 "format=(string){bggr,grbg,gbrg,rggb}");
333 newcaps = gst_caps_new_simple ("video/x-raw-rgb", NULL);
335 newstruct = gst_caps_get_structure (newcaps, 0);
337 gst_structure_set_value (newstruct, "width",
338 gst_structure_get_value (structure, "width"));
339 gst_structure_set_value (newstruct, "height",
340 gst_structure_get_value (structure, "height"));
341 gst_structure_set_value (newstruct, "framerate",
342 gst_structure_get_value (structure, "framerate"));
344 GST_DEBUG_OBJECT (newcaps, "transforming caps (into)");
350 gst_bayer2rgb_get_unit_size (GstBaseTransform * base, GstCaps * caps,
353 GstStructure *structure;
359 structure = gst_caps_get_structure (caps, 0);
361 if (gst_structure_get_int (structure, "width", &width) &&
362 gst_structure_get_int (structure, "height", &height)) {
363 name = gst_structure_get_name (structure);
364 /* Our name must be either video/x-raw-bayer video/x-raw-rgb */
365 if (strcmp (name, "video/x-raw-rgb")) {
366 *size = GST_ROUND_UP_4 (width) * height;
369 /* For output, calculate according to format */
370 if (gst_structure_get_int (structure, "bpp", &pixsize)) {
371 *size = width * height * (pixsize / 8);
377 GST_ELEMENT_ERROR (base, CORE, NEGOTIATION, (NULL),
378 ("Incomplete caps, some required field missing"));
383 gst_bayer2rgb_split_and_upsample_horiz (guint8 * dest0, guint8 * dest1,
384 const guint8 * src, int n)
390 dest0[1] = (src[0] + src[2] + 1) >> 1;
393 #if defined(__i386__) || defined(__amd64__)
394 gst_bayer_horiz_upsample_unaligned (dest0 + 2, dest1 + 2, src + 1,
397 gst_bayer_horiz_upsample (dest0 + 2, dest1 + 2, src + 2, (n - 4) >> 1);
400 for (i = n - 2; i < n; i++) {
403 dest1[i] = src[i - 1];
405 dest0[i] = src[i - 1];
411 typedef void (*process_func) (guint8 * d0, const guint8 * s0, const guint8 * s1,
412 const guint8 * s2, const guint8 * s3, const guint8 * s4, const guint8 * s5,
416 gst_bayer2rgb_process (GstBayer2RGB * bayer2rgb, uint8_t * dest,
417 int dest_stride, uint8_t * src, int src_stride)
421 process_func merge[2] = { NULL, NULL };
422 int r_off, g_off, b_off;
424 /* We exploit some symmetry in the functions here. The base functions
425 * are all named for the BGGR arrangement. For RGGB, we swap the
426 * red offset and blue offset in the output. For GRBG, we swap the
427 * order of the merge functions. For GBRG, do both. */
428 r_off = bayer2rgb->r_off;
429 g_off = bayer2rgb->g_off;
430 b_off = bayer2rgb->b_off;
431 if (bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_RGGB ||
432 bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GBRG) {
433 r_off = bayer2rgb->b_off;
434 b_off = bayer2rgb->r_off;
437 if (r_off == 2 && g_off == 1 && b_off == 0) {
438 merge[0] = gst_bayer_merge_bg_bgra;
439 merge[1] = gst_bayer_merge_gr_bgra;
440 } else if (r_off == 3 && g_off == 2 && b_off == 1) {
441 merge[0] = gst_bayer_merge_bg_abgr;
442 merge[1] = gst_bayer_merge_gr_abgr;
443 } else if (r_off == 1 && g_off == 2 && b_off == 3) {
444 merge[0] = gst_bayer_merge_bg_argb;
445 merge[1] = gst_bayer_merge_gr_argb;
446 } else if (r_off == 0 && g_off == 1 && b_off == 2) {
447 merge[0] = gst_bayer_merge_bg_rgba;
448 merge[1] = gst_bayer_merge_gr_rgba;
450 if (bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GRBG ||
451 bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GBRG) {
452 process_func tmp = merge[0];
457 tmp = g_malloc (2 * 4 * bayer2rgb->width);
458 #define LINE(x) (tmp + ((x)&7) * bayer2rgb->width)
460 gst_bayer2rgb_split_and_upsample_horiz (LINE (3 * 2 + 0), LINE (3 * 2 + 1),
461 src + 1 * src_stride, bayer2rgb->width);
463 gst_bayer2rgb_split_and_upsample_horiz (LINE (j * 2 + 0), LINE (j * 2 + 1),
464 src + j * src_stride, bayer2rgb->width);
466 for (j = 0; j < bayer2rgb->height; j++) {
467 if (j < bayer2rgb->height - 1) {
468 gst_bayer2rgb_split_and_upsample_horiz (LINE ((j + 1) * 2 + 0),
469 LINE ((j + 1) * 2 + 1), src + (j + 1) * src_stride, bayer2rgb->width);
472 merge[j & 1] (dest + j * dest_stride,
473 LINE (j * 2 - 2), LINE (j * 2 - 1),
474 LINE (j * 2 + 0), LINE (j * 2 + 1),
475 LINE (j * 2 + 2), LINE (j * 2 + 3), bayer2rgb->width >> 1);
485 gst_bayer2rgb_transform (GstBaseTransform * base, GstBuffer * inbuf,
488 GstBayer2RGB *filter = GST_BAYER2RGB (base);
489 uint8_t *input, *output;
492 * We need to lock our filter params to prevent changing
493 * caps in the middle of a transformation (nice way to get
496 GST_OBJECT_LOCK (filter);
498 GST_DEBUG ("transforming buffer");
499 input = (uint8_t *) GST_BUFFER_DATA (inbuf);
500 output = (uint8_t *) GST_BUFFER_DATA (outbuf);
501 gst_bayer2rgb_process (filter, output, filter->width * 4,
502 input, filter->width);
504 GST_OBJECT_UNLOCK (filter);