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
28 * Decodes raw camera bayer (fourcc BA81) to RGB.
32 * In order to guard against my advancing maturity, some extra detailed
33 * information about the logic of the decode is included here. Much of
34 * this was inspired by a technical paper from siliconimaging.com, which
35 * in turn was based upon an article from IEEE,
36 * T. Sakamoto, C. Nakanishi and T. Hase,
37 * “Software pixel interpolation for digital still cameras suitable for
39 * IEEE Trans. Consumer Electronics, vol. 44, no. 4, November 1998.
41 * The code assumes a Bayer matrix of the type produced by the fourcc
42 * BA81 (v4l2 format SBGGR8) of width w and height h which looks like:
52 * We expand this matrix, producing a separate {r, g, b} triple for each
53 * of the individual elements. The algorithm for doing this expansion is
56 * We are designing for speed of transformation, at a slight expense of code.
57 * First, we calculate the appropriate triples for the four corners, the
58 * remainder of the top and bottom rows, and the left and right columns.
59 * The reason for this is that those elements are transformed slightly
60 * differently than all of the remainder of the matrix. Finally, we transform
61 * all of the remainder.
63 * The transformation into the "appropriate triples" is based upon the
64 * "nearest neighbor" principal, with some additional complexity for the
65 * calculation of the "green" element, where an "adaptive" pairing is used.
67 * For purposes of documentation and identification, each element of the
68 * original array can be put into one of four classes:
71 * GR A green element which is followed by a red one
72 * GB A green element which is followed by a blue one
80 #include <gst/base/gstbasetransform.h>
81 #include <gst/video/video.h>
89 #include "gstbayerorc.h"
91 #define GST_CAT_DEFAULT gst_bayer2rgb_debug
92 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
96 GST_BAYER_2_RGB_FORMAT_BGGR = 0,
97 GST_BAYER_2_RGB_FORMAT_GBRG,
98 GST_BAYER_2_RGB_FORMAT_GRBG,
99 GST_BAYER_2_RGB_FORMAT_RGGB
103 #define GST_TYPE_BAYER2RGB (gst_bayer2rgb_get_type())
104 #define GST_BAYER2RGB(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BAYER2RGB,GstBayer2RGB))
105 #define GST_IS_BAYER2RGB(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BAYER2RGB))
106 #define GST_BAYER2RGB_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass) ,GST_TYPE_BAYER2RGB,GstBayer2RGBClass))
107 #define GST_IS_BAYER2RGB_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass) ,GST_TYPE_BAYER2RGB))
108 #define GST_BAYER2RGB_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS((obj) ,GST_TYPE_BAYER2RGB,GstBayer2RGBClass))
109 typedef struct _GstBayer2RGB GstBayer2RGB;
110 typedef struct _GstBayer2RGBClass GstBayer2RGBClass;
112 typedef void (*GstBayer2RGBProcessFunc) (GstBayer2RGB *, guint8 *, guint);
116 GstBaseTransform basetransform;
122 int r_off; /* offset for red */
123 int g_off; /* offset for green */
124 int b_off; /* offset for blue */
128 struct _GstBayer2RGBClass
130 GstBaseTransformClass parent;
134 GST_VIDEO_CAPS_MAKE ("{ RGBx, xRGB, BGRx, xBGR, RGBA, ARGB, BGRA, ABGR }")
136 #define SINK_CAPS "video/x-bayer,format=(string){bggr,grbg,gbrg,rggb}," \
137 "width=(int)[1,MAX],height=(int)[1,MAX],framerate=(fraction)[0/1,MAX]"
144 GType gst_bayer2rgb_get_type (void);
146 #define gst_bayer2rgb_parent_class parent_class
147 G_DEFINE_TYPE (GstBayer2RGB, gst_bayer2rgb, GST_TYPE_BASE_TRANSFORM);
149 static void gst_bayer2rgb_set_property (GObject * object, guint prop_id,
150 const GValue * value, GParamSpec * pspec);
151 static void gst_bayer2rgb_get_property (GObject * object, guint prop_id,
152 GValue * value, GParamSpec * pspec);
154 static gboolean gst_bayer2rgb_set_caps (GstBaseTransform * filter,
155 GstCaps * incaps, GstCaps * outcaps);
156 static GstFlowReturn gst_bayer2rgb_transform (GstBaseTransform * base,
157 GstBuffer * inbuf, GstBuffer * outbuf);
158 static void gst_bayer2rgb_reset (GstBayer2RGB * filter);
159 static GstCaps *gst_bayer2rgb_transform_caps (GstBaseTransform * base,
160 GstPadDirection direction, GstCaps * caps, GstCaps * filter);
161 static gboolean gst_bayer2rgb_get_unit_size (GstBaseTransform * base,
162 GstCaps * caps, gsize * size);
166 gst_bayer2rgb_class_init (GstBayer2RGBClass * klass)
168 GObjectClass *gobject_class;
169 GstElementClass *gstelement_class;
171 gobject_class = (GObjectClass *) klass;
172 gstelement_class = (GstElementClass *) klass;
174 gobject_class->set_property = gst_bayer2rgb_set_property;
175 gobject_class->get_property = gst_bayer2rgb_get_property;
177 gst_element_class_set_static_metadata (gstelement_class,
178 "Bayer to RGB decoder for cameras", "Filter/Converter/Video",
179 "Converts video/x-bayer to video/x-raw",
180 "William Brack <wbrack@mmm.com.hk>");
182 gst_element_class_add_pad_template (gstelement_class,
183 gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
184 gst_caps_from_string (SRC_CAPS)));
185 gst_element_class_add_pad_template (gstelement_class,
186 gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
187 gst_caps_from_string (SINK_CAPS)));
189 GST_BASE_TRANSFORM_CLASS (klass)->transform_caps =
190 GST_DEBUG_FUNCPTR (gst_bayer2rgb_transform_caps);
191 GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size =
192 GST_DEBUG_FUNCPTR (gst_bayer2rgb_get_unit_size);
193 GST_BASE_TRANSFORM_CLASS (klass)->set_caps =
194 GST_DEBUG_FUNCPTR (gst_bayer2rgb_set_caps);
195 GST_BASE_TRANSFORM_CLASS (klass)->transform =
196 GST_DEBUG_FUNCPTR (gst_bayer2rgb_transform);
198 GST_DEBUG_CATEGORY_INIT (gst_bayer2rgb_debug, "bayer2rgb", 0,
199 "bayer2rgb element");
203 gst_bayer2rgb_init (GstBayer2RGB * filter)
205 gst_bayer2rgb_reset (filter);
206 gst_base_transform_set_in_place (GST_BASE_TRANSFORM (filter), TRUE);
209 /* No properties are implemented, so only a warning is produced */
211 gst_bayer2rgb_set_property (GObject * object, guint prop_id,
212 const GValue * value, GParamSpec * pspec)
217 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
223 gst_bayer2rgb_get_property (GObject * object, guint prop_id,
224 GValue * value, GParamSpec * pspec)
229 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
235 gst_bayer2rgb_set_caps (GstBaseTransform * base, GstCaps * incaps,
238 GstBayer2RGB *bayer2rgb = GST_BAYER2RGB (base);
239 GstStructure *structure;
243 GST_DEBUG ("in caps %" GST_PTR_FORMAT " out caps %" GST_PTR_FORMAT, incaps,
246 structure = gst_caps_get_structure (incaps, 0);
248 gst_structure_get_int (structure, "width", &bayer2rgb->width);
249 gst_structure_get_int (structure, "height", &bayer2rgb->height);
251 format = gst_structure_get_string (structure, "format");
252 if (g_str_equal (format, "bggr")) {
253 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_BGGR;
254 } else if (g_str_equal (format, "gbrg")) {
255 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_GBRG;
256 } else if (g_str_equal (format, "grbg")) {
257 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_GRBG;
258 } else if (g_str_equal (format, "rggb")) {
259 bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_RGGB;
264 /* To cater for different RGB formats, we need to set params for later */
265 gst_video_info_from_caps (&info, outcaps);
266 bayer2rgb->r_off = GST_VIDEO_INFO_COMP_OFFSET (&info, 0);
267 bayer2rgb->g_off = GST_VIDEO_INFO_COMP_OFFSET (&info, 1);
268 bayer2rgb->b_off = GST_VIDEO_INFO_COMP_OFFSET (&info, 2);
270 bayer2rgb->info = info;
276 gst_bayer2rgb_reset (GstBayer2RGB * filter)
283 gst_video_info_init (&filter->info);
287 gst_bayer2rgb_transform_caps (GstBaseTransform * base,
288 GstPadDirection direction, GstCaps * caps, GstCaps * filter)
290 GstBayer2RGB *bayer2rgb;
291 GstCaps *res_caps, *tmp_caps;
292 GstStructure *structure;
295 bayer2rgb = GST_BAYER2RGB (base);
297 res_caps = gst_caps_copy (caps);
298 caps_size = gst_caps_get_size (res_caps);
299 for (i = 0; i < caps_size; i++) {
300 structure = gst_caps_get_structure (res_caps, i);
301 if (direction == GST_PAD_SINK) {
302 gst_structure_set_name (structure, "video/x-raw");
303 gst_structure_remove_field (structure, "format");
305 gst_structure_set_name (structure, "video/x-bayer");
306 gst_structure_remove_fields (structure, "format", "colorimetry",
307 "chroma-site", NULL);
313 gst_caps_intersect_full (filter, tmp_caps, GST_CAPS_INTERSECT_FIRST);
314 gst_caps_unref (tmp_caps);
316 GST_DEBUG_OBJECT (bayer2rgb, "transformed %" GST_PTR_FORMAT " into %"
317 GST_PTR_FORMAT, caps, res_caps);
322 gst_bayer2rgb_get_unit_size (GstBaseTransform * base, GstCaps * caps,
325 GstStructure *structure;
330 structure = gst_caps_get_structure (caps, 0);
332 if (gst_structure_get_int (structure, "width", &width) &&
333 gst_structure_get_int (structure, "height", &height)) {
334 name = gst_structure_get_name (structure);
335 /* Our name must be either video/x-bayer video/x-raw */
336 if (strcmp (name, "video/x-raw")) {
337 *size = GST_ROUND_UP_4 (width) * height;
340 /* For output, calculate according to format (always 32 bits) */
341 *size = width * height * 4;
346 GST_ELEMENT_ERROR (base, CORE, NEGOTIATION, (NULL),
347 ("Incomplete caps, some required field missing"));
352 gst_bayer2rgb_split_and_upsample_horiz (guint8 * dest0, guint8 * dest1,
353 const guint8 * src, int n)
359 dest0[1] = (src[0] + src[2] + 1) >> 1;
362 #if defined(__i386__) || defined(__amd64__)
363 bayer_orc_horiz_upsample_unaligned (dest0 + 2, dest1 + 2, src + 1,
366 bayer_orc_horiz_upsample (dest0 + 2, dest1 + 2, src + 2, (n - 4) >> 1);
369 for (i = n - 2; i < n; i++) {
372 dest1[i] = src[i - 1];
374 dest0[i] = src[i - 1];
380 typedef void (*process_func) (guint8 * d0, const guint8 * s0, const guint8 * s1,
381 const guint8 * s2, const guint8 * s3, const guint8 * s4, const guint8 * s5,
385 gst_bayer2rgb_process (GstBayer2RGB * bayer2rgb, uint8_t * dest,
386 int dest_stride, uint8_t * src, int src_stride)
390 process_func merge[2] = { NULL, NULL };
391 int r_off, g_off, b_off;
393 /* We exploit some symmetry in the functions here. The base functions
394 * are all named for the BGGR arrangement. For RGGB, we swap the
395 * red offset and blue offset in the output. For GRBG, we swap the
396 * order of the merge functions. For GBRG, do both. */
397 r_off = bayer2rgb->r_off;
398 g_off = bayer2rgb->g_off;
399 b_off = bayer2rgb->b_off;
400 if (bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_RGGB ||
401 bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GBRG) {
402 r_off = bayer2rgb->b_off;
403 b_off = bayer2rgb->r_off;
406 if (r_off == 2 && g_off == 1 && b_off == 0) {
407 merge[0] = bayer_orc_merge_bg_bgra;
408 merge[1] = bayer_orc_merge_gr_bgra;
409 } else if (r_off == 3 && g_off == 2 && b_off == 1) {
410 merge[0] = bayer_orc_merge_bg_abgr;
411 merge[1] = bayer_orc_merge_gr_abgr;
412 } else if (r_off == 1 && g_off == 2 && b_off == 3) {
413 merge[0] = bayer_orc_merge_bg_argb;
414 merge[1] = bayer_orc_merge_gr_argb;
415 } else if (r_off == 0 && g_off == 1 && b_off == 2) {
416 merge[0] = bayer_orc_merge_bg_rgba;
417 merge[1] = bayer_orc_merge_gr_rgba;
419 if (bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GRBG ||
420 bayer2rgb->format == GST_BAYER_2_RGB_FORMAT_GBRG) {
421 process_func tmp = merge[0];
426 tmp = g_malloc (2 * 4 * bayer2rgb->width);
427 #define LINE(x) (tmp + ((x)&7) * bayer2rgb->width)
429 gst_bayer2rgb_split_and_upsample_horiz (LINE (3 * 2 + 0), LINE (3 * 2 + 1),
430 src + 1 * src_stride, bayer2rgb->width);
432 gst_bayer2rgb_split_and_upsample_horiz (LINE (j * 2 + 0), LINE (j * 2 + 1),
433 src + j * src_stride, bayer2rgb->width);
435 for (j = 0; j < bayer2rgb->height; j++) {
436 if (j < bayer2rgb->height - 1) {
437 gst_bayer2rgb_split_and_upsample_horiz (LINE ((j + 1) * 2 + 0),
438 LINE ((j + 1) * 2 + 1), src + (j + 1) * src_stride, bayer2rgb->width);
441 merge[j & 1] (dest + j * dest_stride,
442 LINE (j * 2 - 2), LINE (j * 2 - 1),
443 LINE (j * 2 + 0), LINE (j * 2 + 1),
444 LINE (j * 2 + 2), LINE (j * 2 + 3), bayer2rgb->width >> 1);
454 gst_bayer2rgb_transform (GstBaseTransform * base, GstBuffer * inbuf,
457 GstBayer2RGB *filter = GST_BAYER2RGB (base);
462 GST_DEBUG ("transforming buffer");
464 if (!gst_buffer_map (inbuf, &map, GST_MAP_READ))
467 if (!gst_video_frame_map (&frame, &filter->info, outbuf, GST_MAP_WRITE)) {
468 gst_buffer_unmap (inbuf, &map);
472 output = GST_VIDEO_FRAME_PLANE_DATA (&frame, 0);
473 gst_bayer2rgb_process (filter, output, frame.info.stride[0],
474 map.data, GST_ROUND_UP_4 (filter->width));
476 gst_video_frame_unmap (&frame);
477 gst_buffer_unmap (inbuf, &map);
482 GST_WARNING_OBJECT (base, "Could not map buffer, skipping");