/* * GStreamer * Copyright (C) 2007 David Schleef * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. * * March 2008 * Logic enhanced by William Brack */ /** * SECTION:element-bayer2rgb * * Decodes raw camera bayer (fourcc BA81) to RGB. */ /* * In order to guard against my advancing maturity, some extra detailed * information about the logic of the decode is included here. Much of * this was inspired by a technical paper from siliconimaging.com, which * in turn was based upon an article from IEEE, * T. Sakamoto, C. Nakanishi and T. Hase, * “Software pixel interpolation for digital still cameras suitable for * a 32-bit MCU,” * IEEE Trans. Consumer Electronics, vol. 44, no. 4, November 1998. * * The code assumes a Bayer matrix of the type produced by the fourcc * BA81 (v4l2 format SBGGR8) of width w and height h which looks like: * 0 1 2 3 w-2 w-1 * * 0 B G B G ....B G * 1 G R G R ....G R * 2 B G B G ....B G * ............... * h-2 B G B G ....B G * h-1 G R G R ....G R * * We expand this matrix, producing a separate {r, g, b} triple for each * of the individual elements. The algorithm for doing this expansion is * as follows. * * We are designing for speed of transformation, at a slight expense of code. * First, we calculate the appropriate triples for the four corners, the * remainder of the top and bottom rows, and the left and right columns. * The reason for this is that those elements are transformed slightly * differently than all of the remainder of the matrix. Finally, we transform * all of the remainder. * * The transformation into the "appropriate triples" is based upon the * "nearest neighbor" principal, with some additional complexity for the * calculation of the "green" element, where an "adaptive" pairing is used. * * For purposes of documentation and indentification, each element of the * original array can be put into one of four classes: * R A red element * B A blue element * GR A green element which is followed by a red one * GB A green element which is followed by a blue one */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include #include #include "_stdint.h" #define GST_CAT_DEFAULT gst_bayer2rgb_debug GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT); #define GST_TYPE_BAYER2RGB (gst_bayer2rgb_get_type()) #define GST_BAYER2RGB(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BAYER2RGB,GstBayer2RGB)) #define GST_IS_BAYER2RGB(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BAYER2RGB)) #define GST_BAYER2RGB_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass) ,GST_TYPE_BAYER2RGB,GstBayer2RGBClass)) #define GST_IS_BAYER2RGB_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass) ,GST_TYPE_BAYER2RGB)) #define GST_BAYER2RGB_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS((obj) ,GST_TYPE_BAYER2RGB,GstBayer2RGBClass)) typedef struct _GstBayer2RGB GstBayer2RGB; typedef struct _GstBayer2RGBClass GstBayer2RGBClass; typedef void (*GstBayer2RGBProcessFunc) (GstBayer2RGB *, guint8 *, guint); struct _GstBayer2RGB { GstBaseTransform basetransform; /* < private > */ int width; int height; int stride; int pixsize; /* bytes per pixel */ int r_off; /* offset for red */ int g_off; /* offset for green */ int b_off; /* offset for blue */ }; struct _GstBayer2RGBClass { GstBaseTransformClass parent; }; static const GstElementDetails element_details = GST_ELEMENT_DETAILS ("Bayer to RGB decoder for cameras", "Filter/Converter/Video", "Converts video/x-raw-bayer to video/x-raw-rgb", "William Brack "); //#define SRC_CAPS GST_VIDEO_CAPS_RGBx #define SRC_CAPS \ GST_VIDEO_CAPS_RGBx ";" \ GST_VIDEO_CAPS_xRGB ";" \ GST_VIDEO_CAPS_BGRx ";" \ GST_VIDEO_CAPS_xBGR ";" \ GST_VIDEO_CAPS_RGBA ";" \ GST_VIDEO_CAPS_ARGB ";" \ GST_VIDEO_CAPS_BGRA ";" \ GST_VIDEO_CAPS_ABGR ";" \ GST_VIDEO_CAPS_RGB ";" \ GST_VIDEO_CAPS_BGR #define SINK_CAPS "video/x-raw-bayer,width=(int)[1,MAX],height=(int)[1,MAX]" enum { PROP_0 }; #define DEBUG_INIT(bla) \ GST_DEBUG_CATEGORY_INIT (gst_bayer2rgb_debug, "bayer2rgb", 0, "bayer2rgb element"); GST_BOILERPLATE_FULL (GstBayer2RGB, gst_bayer2rgb, GstBaseTransform, GST_TYPE_BASE_TRANSFORM, DEBUG_INIT); static void gst_bayer2rgb_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_bayer2rgb_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static gboolean gst_bayer2rgb_set_caps (GstBaseTransform * filter, GstCaps * incaps, GstCaps * outcaps); static GstFlowReturn gst_bayer2rgb_transform (GstBaseTransform * base, GstBuffer * inbuf, GstBuffer * outbuf); static void gst_bayer2rgb_reset (GstBayer2RGB * filter); static GstCaps *gst_bayer2rgb_transform_caps (GstBaseTransform * base, GstPadDirection direction, GstCaps * caps); static gboolean gst_bayer2rgb_get_unit_size (GstBaseTransform * base, GstCaps * caps, guint * size); static void gst_bayer2rgb_base_init (gpointer klass) { GstElementClass *element_class = GST_ELEMENT_CLASS (klass); gst_element_class_set_details (element_class, &element_details); gst_element_class_add_pad_template (element_class, gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS, gst_caps_from_string (SRC_CAPS))); gst_element_class_add_pad_template (element_class, gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, gst_caps_from_string (SINK_CAPS))); } static void gst_bayer2rgb_class_init (GstBayer2RGBClass * klass) { GObjectClass *gobject_class; gobject_class = (GObjectClass *) klass; gobject_class->set_property = gst_bayer2rgb_set_property; gobject_class->get_property = gst_bayer2rgb_get_property; GST_BASE_TRANSFORM_CLASS (klass)->transform_caps = GST_DEBUG_FUNCPTR (gst_bayer2rgb_transform_caps); GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size = GST_DEBUG_FUNCPTR (gst_bayer2rgb_get_unit_size); GST_BASE_TRANSFORM_CLASS (klass)->set_caps = GST_DEBUG_FUNCPTR (gst_bayer2rgb_set_caps); GST_BASE_TRANSFORM_CLASS (klass)->transform = GST_DEBUG_FUNCPTR (gst_bayer2rgb_transform); } static void gst_bayer2rgb_init (GstBayer2RGB * filter, GstBayer2RGBClass * klass) { gst_bayer2rgb_reset (filter); gst_base_transform_set_in_place (GST_BASE_TRANSFORM (filter), TRUE); } /* No properties are implemented, so only a warning is produced */ static void gst_bayer2rgb_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { switch (prop_id) { default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_bayer2rgb_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { switch (prop_id) { default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } /* Routine to convert colormask value into relative byte offset */ static int get_pix_offset (int mask, int bpp) { int bpp32 = (bpp / 8) - 3; switch (mask) { case 255: return 2 + bpp32; case 65280: return 1 + bpp32; case 16711680: return 0 + bpp32; case -16777216: return 0; default: GST_ERROR ("Invalid color mask 0x%08x", mask); return -1; } } static gboolean gst_bayer2rgb_set_caps (GstBaseTransform * base, GstCaps * incaps, GstCaps * outcaps) { GstBayer2RGB *filter = GST_BAYER2RGB (base); GstStructure *structure; int val, bpp; GST_DEBUG ("in caps %" GST_PTR_FORMAT " out caps %" GST_PTR_FORMAT, incaps, outcaps); structure = gst_caps_get_structure (incaps, 0); gst_structure_get_int (structure, "width", &filter->width); gst_structure_get_int (structure, "height", &filter->height); filter->stride = GST_ROUND_UP_4 (filter->width); /* To cater for different RGB formats, we need to set params for later */ structure = gst_caps_get_structure (outcaps, 0); gst_structure_get_int (structure, "bpp", &bpp); filter->pixsize = bpp / 8; gst_structure_get_int (structure, "red_mask", &val); filter->r_off = get_pix_offset (val, bpp); gst_structure_get_int (structure, "green_mask", &val); filter->g_off = get_pix_offset (val, bpp); gst_structure_get_int (structure, "blue_mask", &val); filter->b_off = get_pix_offset (val, bpp); return TRUE; } static void gst_bayer2rgb_reset (GstBayer2RGB * filter) { filter->width = 0; filter->height = 0; filter->stride = 0; filter->pixsize = 0; filter->r_off = 0; filter->g_off = 0; filter->b_off = 0; } static GstCaps * gst_bayer2rgb_transform_caps (GstBaseTransform * base, GstPadDirection direction, GstCaps * caps) { GstStructure *structure; GstCaps *newcaps; GstStructure *newstruct; GST_DEBUG_OBJECT (caps, "transforming caps (from)"); structure = gst_caps_get_structure (caps, 0); if (direction == GST_PAD_SRC) { newcaps = gst_caps_new_simple ("video/x-raw-bayer", NULL); } else { newcaps = gst_caps_new_simple ("video/x-raw-rgb", NULL); } newstruct = gst_caps_get_structure (newcaps, 0); gst_structure_set_value (newstruct, "width", gst_structure_get_value (structure, "width")); gst_structure_set_value (newstruct, "height", gst_structure_get_value (structure, "height")); gst_structure_set_value (newstruct, "framerate", gst_structure_get_value (structure, "framerate")); GST_DEBUG_OBJECT (newcaps, "transforming caps (into)"); return newcaps; } static gboolean gst_bayer2rgb_get_unit_size (GstBaseTransform * base, GstCaps * caps, guint * size) { GstStructure *structure; int width; int height; int pixsize; const char *name; structure = gst_caps_get_structure (caps, 0); if (gst_structure_get_int (structure, "width", &width) && gst_structure_get_int (structure, "height", &height)) { name = gst_structure_get_name (structure); /* Our name must be either video/x-raw-bayer video/x-raw-rgb */ if (strcmp (name, "video/x-raw-rgb")) { /* For bayer, we handle only BA81 (BGGR), which is BPP=24 */ *size = GST_ROUND_UP_4 (width) * height; return TRUE; } else { /* For output, calculate according to format */ if (gst_structure_get_int (structure, "bpp", &pixsize)) { *size = width * height * (pixsize / 8); return TRUE; } } } GST_ELEMENT_ERROR (base, CORE, NEGOTIATION, (NULL), ("Incomplete caps, some required field missing")); return FALSE; } /* * We define values for the colors, just to make the code more readable. */ #define RED 0 /* Pure red element */ #define GREENB 1 /* Green element which is on a blue line */ #define BLUE 2 /* Pure blue element */ #define GREENR 3 /* Green element which is on a red line */ /* Routine to generate the top and bottom edges (not including corners) */ static void hborder (uint8_t * input, uint8_t * output, int bot_top, int typ, GstBayer2RGB * filter) { uint8_t *op; /* output pointer */ uint8_t *ip; /* input pointer */ uint8_t *nx; /* next line pointer */ int ix; /* loop index */ op = output + (bot_top * filter->width * (filter->height - 1) + 1) * filter->pixsize; ip = input + bot_top * filter->stride * (filter->height - 1); /* calculate minus or plus one line, depending upon bot_top flag */ nx = ip + (1 - 2 * bot_top) * filter->stride; /* Stepping horizontally */ for (ix = 1; ix < filter->width - 1; ix++, op += filter->pixsize) { switch (typ) { case RED: op[filter->r_off] = ip[ix]; op[filter->g_off] = (ip[ix + 1] + ip[ix - 1] + nx[ix] + 1) / 3; op[filter->b_off] = (nx[ix + 1] + nx[ix - 1] + 1) / 2; typ = GREENR; break; case GREENR: op[filter->r_off] = (ip[ix + 1] + ip[ix - 1] + 1) / 2; op[filter->g_off] = ip[ix]; op[filter->b_off] = nx[ix]; typ = RED; break; case GREENB: op[filter->r_off] = nx[ix]; op[filter->g_off] = ip[ix]; op[filter->b_off] = (ip[ix + 1] + ip[ix - 1] + 1) / 2; typ = BLUE; break; case BLUE: op[filter->r_off] = (nx[ix + 1] + nx[ix - 1] + 1) / 2; op[filter->g_off] = (ip[ix + 1] + ip[ix - 1] + nx[ix] + 1) / 3; op[filter->b_off] = ip[ix]; typ = GREENB; break; } } } /* Routine to generate the left and right edges, not including corners */ static void vborder (uint8_t * input, uint8_t * output, int right_left, int typ, GstBayer2RGB * filter) { uint8_t *op; /* output pointer */ uint8_t *ip; /* input pointer */ uint8_t *la; /* line above pointer */ uint8_t *lb; /* line below pointer */ int ix; /* loop index */ int lr; /* 'left-right' flag - +1 is right, -1 is left */ lr = (1 - 2 * right_left); /* stepping vertically */ for (ix = 1; ix < filter->height - 1; ix++) { ip = input + right_left * (filter->width - 1) + ix * filter->stride; op = output + (right_left * (filter->width - 1) + ix * filter->width) * filter->pixsize; la = ip + filter->stride; lb = ip - filter->stride; switch (typ) { case RED: op[filter->r_off] = ip[0]; op[filter->g_off] = (la[0] + ip[lr] + lb[0] + 1) / 3; op[filter->b_off] = (la[lr] + lb[lr] + 1) / 2; typ = GREENB; break; case GREENR: op[filter->r_off] = ip[lr]; op[filter->g_off] = ip[0]; op[filter->b_off] = (la[lr] + lb[lr] + 1) / 2; typ = BLUE; break; case GREENB: op[filter->r_off] = (la[lr] + lb[lr] + 1) / 2; op[filter->g_off] = ip[0]; op[filter->b_off] = ip[lr]; typ = RED; break; case BLUE: op[filter->r_off] = (la[lr] + lb[lr] + 1) / 2; op[filter->g_off] = (la[0] + ip[lr] + lb[0] + 1) / 3; op[filter->b_off] = ip[0]; typ = GREENR; break; } } } /* Produce the four (top, bottom, left, right) edges */ static void do_row0_col0 (uint8_t * input, uint8_t * output, GstBayer2RGB * filter) { int type; /* Horizontal edges */ hborder (input, output, 0, GREENB, filter); if (filter->height & 1) type = GREENB; /* odd # rows, "bottom" edge same as top */ else type = RED; /* even #, bottom side different */ hborder (input, output, 1, type, filter); /* Vertical edges */ vborder (input, output, 0, GREENR, filter); if (filter->width & 1) type = GREENR; /* odd # cols, "right" edge same as left */ else type = RED; /* even #, right side different */ vborder (input, output, 1, type, filter); } static void corner (uint8_t * input, uint8_t * output, int x, int y, int xd, int yd, int typ, GstBayer2RGB * filter) { uint8_t *ip; /* input pointer */ uint8_t *op; /* output pointer */ uint8_t *nx; /* adjacent line */ op = output + y * filter->width * filter->pixsize + x * filter->pixsize; ip = input + y * filter->stride + x; nx = ip + yd * filter->stride; switch (typ) { case RED: op[filter->r_off] = ip[0]; op[filter->g_off] = (nx[0] + ip[xd] + 1) / 2; op[filter->b_off] = nx[xd]; break; case GREENR: op[filter->r_off] = ip[xd]; op[filter->g_off] = ip[0]; op[filter->b_off] = nx[0]; break; case GREENB: op[filter->r_off] = nx[0]; op[filter->g_off] = ip[0]; op[filter->b_off] = ip[xd]; break; case BLUE: op[filter->r_off] = nx[xd]; op[filter->g_off] = (nx[0] + ip[xd] + 1) / 2; op[filter->b_off] = ip[0]; break; } } static void do_corners (uint8_t * input, uint8_t * output, GstBayer2RGB * filter) { int typ; /* Top left */ corner (input, output, 0, 0, 1, 1, BLUE, filter); /* Bottom left */ corner (input, output, 0, filter->height - 1, 1, -1, (filter->height & 1) ? BLUE : GREENR, filter); /* Top right */ corner (input, output, filter->width - 1, 0, -1, 0, (filter->width & 1) ? BLUE : GREENB, filter); /* Bottom right */ if (filter->width & 1) /* if odd # cols, B or GB */ typ = BLUE; else typ = GREENB; /* if even # cols, B or GR */ typ |= (filter->height & 1); /* if odd # rows, GB or GR */ corner (input, output, filter->width - 1, filter->height - 1, -1, -1, typ, filter); } static void do_body (uint8_t * input, uint8_t * output, GstBayer2RGB * filter) { int ip, op; /* input and output pointers */ int w, h; /* loop indices */ int type; /* calculated colour of current element */ int a1, a2; int v1, v2, h1, h2; /* * We are processing row (line) by row, starting with the second * row and continuing through the next to last. Each row is processed * column by column, starting with the second and continuing through * to the next to last. */ for (h = 1; h < filter->height - 1; h++) { /* * Remember we are processing "row by row". For each row, we need * to set the type of the first element to be processed. Since we * have already processed the edges, the "first element" will be * the pixel at position (1,1). Assuming BG format, this should * be RED for odd-numbered rows and GREENB for even rows. */ if (h & 1) type = RED; else type = GREENB; /* Calculate the starting position for the row */ op = h * filter->width * filter->pixsize; /* output (converted) pos */ ip = h * filter->stride; /* input (bayer data) pos */ for (w = 1; w < filter->width - 1; w++) { op += filter->pixsize; /* we are processing "horizontally" */ ip++; switch (type) { case RED: output[op + filter->r_off] = input[ip]; output[op + filter->b_off] = (input[ip - filter->stride - 1] + input[ip - filter->stride + 1] + input[ip + filter->stride - 1] + input[ip + filter->stride + 1] + 2) / 4; v1 = input[ip + filter->stride]; v2 = input[ip - filter->stride]; h1 = input[ip + 1]; h2 = input[ip - 1]; a1 = abs (v1 - v2); a2 = abs (h1 - h2); if (a1 < a2) output[op + filter->g_off] = (v1 + v2 + 1) / 2; else if (a1 > a2) output[op + filter->g_off] = (h1 + h2 + 1) / 2; else output[op + filter->g_off] = (v1 + h1 + v2 + h2 + 2) / 4; type = GREENR; break; case GREENR: output[op + filter->r_off] = (input[ip + 1] + input[ip - 1] + 1) / 2; output[op + filter->g_off] = input[ip]; output[op + filter->b_off] = (input[ip - filter->stride] + input[ip + filter->stride] + 1) / 2; type = RED; break; case GREENB: output[op + filter->r_off] = (input[ip - filter->stride] + input[ip + filter->stride] + 1) / 2; output[op + filter->g_off] = input[ip]; output[op + filter->b_off] = (input[ip + 1] + input[ip - 1] + 1) / 2; type = BLUE; break; case BLUE: output[op + filter->r_off] = (input[ip - filter->stride - 1] + input[ip - filter->stride + 1] + input[ip + filter->stride - 1] + input[ip + filter->stride + 1] + 2) / 4; output[op + filter->b_off] = input[ip]; v1 = input[ip + filter->stride]; v2 = input[ip - filter->stride]; h1 = input[ip + 1]; h2 = input[ip - 1]; a1 = abs (v1 - v2); a2 = abs (h1 - h2); if (a1 < a2) output[op + filter->g_off] = (v1 + v2 + 1) / 2; else if (a1 > a2) output[op + filter->g_off] = (h1 + h2 + 1) / 2; else output[op + filter->g_off] = (v1 + h1 + v2 + h2 + 2) / 4; type = GREENB; break; } } } } static GstFlowReturn gst_bayer2rgb_transform (GstBaseTransform * base, GstBuffer * inbuf, GstBuffer * outbuf) { GstBayer2RGB *filter = GST_BAYER2RGB (base); uint8_t *input, *output; /* * We need to lock our filter params to prevent changing * caps in the middle of a transformation (nice way to get * segfaults) */ GST_OBJECT_LOCK (filter); GST_DEBUG ("transforming buffer"); input = (uint8_t *) GST_BUFFER_DATA (inbuf); output = (uint8_t *) GST_BUFFER_DATA (outbuf); do_corners (input, output, filter); do_row0_col0 (input, output, filter); do_body (input, output, filter); GST_OBJECT_UNLOCK (filter); return GST_FLOW_OK; }