gstreamer/gst/bayer/gstbayer2rgb.c
2010-06-03 23:57:46 -07:00

684 lines
22 KiB
C

/*
* GStreamer
* Copyright (C) 2007 David Schleef <ds@schleef.org>
*
* 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 <wbrack@mmm.com.hk>
*/
/**
* 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 <gst/gst.h>
#include <gst/base/gstbasetransform.h>
#include <gst/video/video.h>
#include <string.h>
#include <stdlib.h>
#include "_stdint.h"
#define GST_CAT_DEFAULT gst_bayer2rgb_debug
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
enum
{
GST_BAYER_2_RGB_FORMAT_BGGR = 0,
GST_BAYER_2_RGB_FORMAT_GBRG,
GST_BAYER_2_RGB_FORMAT_GRBG,
GST_BAYER_2_RGB_FORMAT_RGGB
};
#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 */
int format;
};
struct _GstBayer2RGBClass
{
GstBaseTransformClass parent;
};
//#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");
GType gst_bayer2rgb_get_type (void);
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_simple (element_class,
"Bayer to RGB decoder for cameras", "Filter/Converter/Video",
"Converts video/x-raw-bayer to video/x-raw-rgb",
"William Brack <wbrack@mmm.com.hk>");
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 *bayer2rgb = GST_BAYER2RGB (base);
GstStructure *structure;
int val, bpp;
const char *format;
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", &bayer2rgb->width);
gst_structure_get_int (structure, "height", &bayer2rgb->height);
bayer2rgb->stride = GST_ROUND_UP_4 (bayer2rgb->width);
format = gst_structure_get_string (structure, "format");
if (g_str_equal (format, "bggr")) {
bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_BGGR;
} else if (g_str_equal (format, "gbrg")) {
bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_GBRG;
} else if (g_str_equal (format, "grbg")) {
bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_GRBG;
} else if (g_str_equal (format, "rggb")) {
bayer2rgb->format = GST_BAYER_2_RGB_FORMAT_RGGB;
} else {
return FALSE;
}
/* 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);
bayer2rgb->pixsize = bpp / 8;
gst_structure_get_int (structure, "red_mask", &val);
bayer2rgb->r_off = get_pix_offset (val, bpp);
gst_structure_get_int (structure, "green_mask", &val);
bayer2rgb->g_off = get_pix_offset (val, bpp);
gst_structure_get_int (structure, "blue_mask", &val);
bayer2rgb->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 */
static int
get_pixel_type (GstBayer2RGB * filter, int x, int y)
{
int type;
if (((x ^ filter->format) & 1)) {
if ((y ^ (filter->format >> 1)) & 1)
type = RED;
else
type = GREENB;
} else {
if ((y ^ (filter->format >> 1)) & 1)
type = GREENR;
else
type = BLUE;
}
return type;
}
/* 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)
{
/* Horizontal edges */
hborder (input, output, 0, get_pixel_type (filter, 1, 0), filter);
hborder (input, output, 1, get_pixel_type (filter, 1, filter->height - 1),
filter);
/* Vertical edges */
vborder (input, output, 0, get_pixel_type (filter, 0, 1), filter);
vborder (input, output, 1, get_pixel_type (filter, filter->width - 1, 1),
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)
{
/* Top left */
corner (input, output, 0, 0, 1, 1, get_pixel_type (filter, 0, 0), filter);
/* Bottom left */
corner (input, output, 0, filter->height - 1, 1, -1,
get_pixel_type (filter, 0, filter->height - 1), filter);
/* Top right */
corner (input, output, filter->width - 1, 0, -1, 0,
get_pixel_type (filter, filter->width - 1, 0), filter);
/* Bottom right */
corner (input, output, filter->width - 1, filter->height - 1, -1, -1,
get_pixel_type (filter, filter->width - 1, filter->height - 1), 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.
*/
type = get_pixel_type (filter, 1, h);
/* 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;
}