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., 51 Franklin St, Fifth Floor,
18 * Boston, MA 02110-1301, 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>
88 #include "gstbayerorc.h"
90 #define GST_CAT_DEFAULT gst_bayer2rgb_debug
91 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
95 GST_BAYER_2_RGB_FORMAT_BGGR = 0,
96 GST_BAYER_2_RGB_FORMAT_GBRG,
97 GST_BAYER_2_RGB_FORMAT_GRBG,
98 GST_BAYER_2_RGB_FORMAT_RGGB
102 #define GST_TYPE_BAYER2RGB (gst_bayer2rgb_get_type())
103 #define GST_BAYER2RGB(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BAYER2RGB,GstBayer2RGB))
104 #define GST_IS_BAYER2RGB(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BAYER2RGB))
105 #define GST_BAYER2RGB_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass) ,GST_TYPE_BAYER2RGB,GstBayer2RGBClass))
106 #define GST_IS_BAYER2RGB_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass) ,GST_TYPE_BAYER2RGB))
107 #define GST_BAYER2RGB_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS((obj) ,GST_TYPE_BAYER2RGB,GstBayer2RGBClass))
108 typedef struct _GstBayer2RGB GstBayer2RGB;
109 typedef struct _GstBayer2RGBClass GstBayer2RGBClass;
111 typedef void (*GstBayer2RGBProcessFunc) (GstBayer2RGB *, guint8 *, guint);
115 GstBaseTransform basetransform;
121 int r_off; /* offset for red */
122 int g_off; /* offset for green */
123 int b_off; /* offset for blue */
127 struct _GstBayer2RGBClass
129 GstBaseTransformClass parent;
133 GST_VIDEO_CAPS_MAKE ("{ RGBx, xRGB, BGRx, xBGR, RGBA, ARGB, BGRA, ABGR }")
135 #define SINK_CAPS "video/x-bayer,format=(string){bggr,grbg,gbrg,rggb}," \
136 "width=(int)[1,MAX],height=(int)[1,MAX],framerate=(fraction)[0/1,MAX]"
143 GType gst_bayer2rgb_get_type (void);
145 #define gst_bayer2rgb_parent_class parent_class
146 G_DEFINE_TYPE (GstBayer2RGB, gst_bayer2rgb, GST_TYPE_BASE_TRANSFORM);
148 static void gst_bayer2rgb_set_property (GObject * object, guint prop_id,
149 const GValue * value, GParamSpec * pspec);
150 static void gst_bayer2rgb_get_property (GObject * object, guint prop_id,
151 GValue * value, GParamSpec * pspec);
153 static gboolean gst_bayer2rgb_set_caps (GstBaseTransform * filter,
154 GstCaps * incaps, GstCaps * outcaps);
155 static GstFlowReturn gst_bayer2rgb_transform (GstBaseTransform * base,
156 GstBuffer * inbuf, GstBuffer * outbuf);
157 static void gst_bayer2rgb_reset (GstBayer2RGB * filter);
158 static GstCaps *gst_bayer2rgb_transform_caps (GstBaseTransform * base,
159 GstPadDirection direction, GstCaps * caps, GstCaps * filter);
160 static gboolean gst_bayer2rgb_get_unit_size (GstBaseTransform * base,
161 GstCaps * caps, gsize * size);
165 gst_bayer2rgb_class_init (GstBayer2RGBClass * klass)
167 GObjectClass *gobject_class;
168 GstElementClass *gstelement_class;
170 gobject_class = (GObjectClass *) klass;
171 gstelement_class = (GstElementClass *) klass;
173 gobject_class->set_property = gst_bayer2rgb_set_property;
174 gobject_class->get_property = gst_bayer2rgb_get_property;
176 gst_element_class_set_static_metadata (gstelement_class,
177 "Bayer to RGB decoder for cameras", "Filter/Converter/Video",
178 "Converts video/x-bayer to video/x-raw",
179 "William Brack <wbrack@mmm.com.hk>");
181 gst_element_class_add_pad_template (gstelement_class,
182 gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
183 gst_caps_from_string (SRC_CAPS)));
184 gst_element_class_add_pad_template (gstelement_class,
185 gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
186 gst_caps_from_string (SINK_CAPS)));
188 GST_BASE_TRANSFORM_CLASS (klass)->transform_caps =
189 GST_DEBUG_FUNCPTR (gst_bayer2rgb_transform_caps);
190 GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size =
191 GST_DEBUG_FUNCPTR (gst_bayer2rgb_get_unit_size);
192 GST_BASE_TRANSFORM_CLASS (klass)->set_caps =
193 GST_DEBUG_FUNCPTR (gst_bayer2rgb_set_caps);
194 GST_BASE_TRANSFORM_CLASS (klass)->transform =
195 GST_DEBUG_FUNCPTR (gst_bayer2rgb_transform);
197 GST_DEBUG_CATEGORY_INIT (gst_bayer2rgb_debug, "bayer2rgb", 0,
198 "bayer2rgb element");
202 gst_bayer2rgb_init (GstBayer2RGB * filter)
204 gst_bayer2rgb_reset (filter);
205 gst_base_transform_set_in_place (GST_BASE_TRANSFORM (filter), TRUE);
208 /* No properties are implemented, so only a warning is produced */
210 gst_bayer2rgb_set_property (GObject * object, guint prop_id,
211 const GValue * value, GParamSpec * pspec)
216 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
222 gst_bayer2rgb_get_property (GObject * object, guint prop_id,
223 GValue * value, GParamSpec * pspec)
228 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
234 gst_bayer2rgb_set_caps (GstBaseTransform * base, GstCaps * incaps,
237 GstBayer2RGB *bayer2rgb = GST_BAYER2RGB (base);
238 GstStructure *structure;
242 GST_DEBUG ("in caps %" GST_PTR_FORMAT " out caps %" GST_PTR_FORMAT, incaps,
245 structure = gst_caps_get_structure (incaps, 0);
247 gst_structure_get_int (structure, "width", &bayer2rgb->width);
248 gst_structure_get_int (structure, "height", &bayer2rgb->height);
250 format = gst_structure_get_string (structure, "format");
251 if (g_str_equal (format, "bggr")) {
252 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_BGGR;
253 } else if (g_str_equal (format, "gbrg")) {
254 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_GBRG;
255 } else if (g_str_equal (format, "grbg")) {
256 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_GRBG;
257 } else if (g_str_equal (format, "rggb")) {
258 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_RGGB;
263 /* To cater for different RGB formats, we need to set params for later */
264 gst_video_info_from_caps (&info, outcaps);
265 bayer2rgb->r_off = GST_VIDEO_INFO_COMP_OFFSET (&info, 0);
266 bayer2rgb->g_off = GST_VIDEO_INFO_COMP_OFFSET (&info, 1);
267 bayer2rgb->b_off = GST_VIDEO_INFO_COMP_OFFSET (&info, 2);
269 bayer2rgb->info = info;
275 gst_bayer2rgb_reset (GstBayer2RGB * filter)
282 gst_video_info_init (&filter->info);
286 gst_bayer2rgb_transform_caps (GstBaseTransform * base,
287 GstPadDirection direction, GstCaps * caps, GstCaps * filter)
289 GstBayer2RGB *bayer2rgb;
290 GstCaps *res_caps, *tmp_caps;
291 GstStructure *structure;
294 bayer2rgb = GST_BAYER2RGB (base);
296 res_caps = gst_caps_copy (caps);
297 caps_size = gst_caps_get_size (res_caps);
298 for (i = 0; i < caps_size; i++) {
299 structure = gst_caps_get_structure (res_caps, i);
300 if (direction == GST_PAD_SINK) {
301 gst_structure_set_name (structure, "video/x-raw");
302 gst_structure_remove_field (structure, "format");
304 gst_structure_set_name (structure, "video/x-bayer");
305 gst_structure_remove_fields (structure, "format", "colorimetry",
306 "chroma-site", NULL);
312 gst_caps_intersect_full (filter, tmp_caps, GST_CAPS_INTERSECT_FIRST);
313 gst_caps_unref (tmp_caps);
315 GST_DEBUG_OBJECT (bayer2rgb, "transformed %" GST_PTR_FORMAT " into %"
316 GST_PTR_FORMAT, caps, res_caps);
321 gst_bayer2rgb_get_unit_size (GstBaseTransform * base, GstCaps * caps,
324 GstStructure *structure;
329 structure = gst_caps_get_structure (caps, 0);
331 if (gst_structure_get_int (structure, "width", &width) &&
332 gst_structure_get_int (structure, "height", &height)) {
333 name = gst_structure_get_name (structure);
334 /* Our name must be either video/x-bayer video/x-raw */
335 if (strcmp (name, "video/x-raw")) {
336 *size = GST_ROUND_UP_4 (width) * height;
339 /* For output, calculate according to format (always 32 bits) */
340 *size = width * height * 4;
345 GST_ELEMENT_ERROR (base, CORE, NEGOTIATION, (NULL),
346 ("Incomplete caps, some required field missing"));
351 gst_bayer2rgb_split_and_upsample_horiz (guint8 * dest0, guint8 * dest1,
352 const guint8 * src, int n)
358 dest0[1] = (src[0] + src[2] + 1) >> 1;
361 #if defined(__i386__) || defined(__amd64__)
362 bayer_orc_horiz_upsample_unaligned (dest0 + 2, dest1 + 2, src + 1,
365 bayer_orc_horiz_upsample (dest0 + 2, dest1 + 2, src + 2, (n - 4) >> 1);
368 for (i = n - 2; i < n; i++) {
371 dest1[i] = src[i - 1];
373 dest0[i] = src[i - 1];
379 typedef void (*process_func) (guint8 * d0, const guint8 * s0, const guint8 * s1,
380 const guint8 * s2, const guint8 * s3, const guint8 * s4, const guint8 * s5,
384 gst_bayer2rgb_process (GstBayer2RGB * bayer2rgb, uint8_t * dest,
385 int dest_stride, uint8_t * src, int src_stride)
389 process_func merge[2] = { NULL, NULL };
390 int r_off, g_off, b_off;
392 /* We exploit some symmetry in the functions here. The base functions
393 * are all named for the BGGR arrangement. For RGGB, we swap the
394 * red offset and blue offset in the output. For GRBG, we swap the
395 * order of the merge functions. For GBRG, do both. */
396 r_off = bayer2rgb->r_off;
397 g_off = bayer2rgb->g_off;
398 b_off = bayer2rgb->b_off;
399 if (bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_RGGB ||
400 bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GBRG) {
401 r_off = bayer2rgb->b_off;
402 b_off = bayer2rgb->r_off;
405 if (r_off == 2 && g_off == 1 && b_off == 0) {
406 merge[0] = bayer_orc_merge_bg_bgra;
407 merge[1] = bayer_orc_merge_gr_bgra;
408 } else if (r_off == 3 && g_off == 2 && b_off == 1) {
409 merge[0] = bayer_orc_merge_bg_abgr;
410 merge[1] = bayer_orc_merge_gr_abgr;
411 } else if (r_off == 1 && g_off == 2 && b_off == 3) {
412 merge[0] = bayer_orc_merge_bg_argb;
413 merge[1] = bayer_orc_merge_gr_argb;
414 } else if (r_off == 0 && g_off == 1 && b_off == 2) {
415 merge[0] = bayer_orc_merge_bg_rgba;
416 merge[1] = bayer_orc_merge_gr_rgba;
418 if (bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GRBG ||
419 bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GBRG) {
420 process_func tmp = merge[0];
425 tmp = g_malloc (2 * 4 * bayer2rgb->width);
426 #define LINE(x) (tmp + ((x)&7) * bayer2rgb->width)
428 gst_bayer2rgb_split_and_upsample_horiz (LINE (3 * 2 + 0), LINE (3 * 2 + 1),
429 src + 1 * src_stride, bayer2rgb->width);
431 gst_bayer2rgb_split_and_upsample_horiz (LINE (j * 2 + 0), LINE (j * 2 + 1),
432 src + j * src_stride, bayer2rgb->width);
434 for (j = 0; j < bayer2rgb->height; j++) {
435 if (j < bayer2rgb->height - 1) {
436 gst_bayer2rgb_split_and_upsample_horiz (LINE ((j + 1) * 2 + 0),
437 LINE ((j + 1) * 2 + 1), src + (j + 1) * src_stride, bayer2rgb->width);
440 merge[j & 1] (dest + j * dest_stride,
441 LINE (j * 2 - 2), LINE (j * 2 - 1),
442 LINE (j * 2 + 0), LINE (j * 2 + 1),
443 LINE (j * 2 + 2), LINE (j * 2 + 3), bayer2rgb->width >> 1);
453 gst_bayer2rgb_transform (GstBaseTransform * base, GstBuffer * inbuf,
456 GstBayer2RGB *filter = GST_BAYER2RGB (base);
461 GST_DEBUG ("transforming buffer");
463 if (!gst_buffer_map (inbuf, &map, GST_MAP_READ))
466 if (!gst_video_frame_map (&frame, &filter->info, outbuf, GST_MAP_WRITE)) {
467 gst_buffer_unmap (inbuf, &map);
471 output = GST_VIDEO_FRAME_PLANE_DATA (&frame, 0);
472 gst_bayer2rgb_process (filter, output, frame.info.stride[0],
473 map.data, GST_ROUND_UP_4 (filter->width));
475 gst_video_frame_unmap (&frame);
476 gst_buffer_unmap (inbuf, &map);
481 GST_WARNING_OBJECT (base, "Could not map buffer, skipping");