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gst/alpha/gstalpha.c: Implement alpha functions for AYUV too, this increases accuracy quite a bit.

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Original commit message from CVS:
* gst/alpha/gstalpha.c: (gst_alpha_method_get_type),
(gst_alpha_set_property), (gst_alpha_sink_link),
(gst_alpha_set_ayuv), (gst_alpha_set_i420),
(gst_alpha_chroma_key_ayuv), (gst_alpha_chroma_key_i420),
(gst_alpha_init_params), (gst_alpha_chain):
Implement alpha functions for AYUV too, this increases
accuracy quite a bit.
This commit is contained in:
Wim Taymans 2004-11-08 16:16:10 +00:00
parent 71fbda134d
commit 71ebb1575a
2 changed files with 193 additions and 19 deletions
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10
ChangeLog
View file

@ -1,3 +1,13 @@
2004-11-08 Wim Taymans <wim@fluendo.com>
* gst/alpha/gstalpha.c: (gst_alpha_method_get_type),
(gst_alpha_set_property), (gst_alpha_sink_link),
(gst_alpha_set_ayuv), (gst_alpha_set_i420),
(gst_alpha_chroma_key_ayuv), (gst_alpha_chroma_key_i420),
(gst_alpha_init_params), (gst_alpha_chain):
Implement alpha functions for AYUV too, this increases
accuracy quite a bit.
2004-11-08 Wim Taymans <wim@fluendo.com>
* gst/ffmpegcolorspace/avcodec.h:

202
gst/alpha/gstalpha.c
View file

@ -42,7 +42,7 @@ typedef struct _GstAlphaClass GstAlphaClass;
typedef enum
{
ALPHA_METHOD_ADD,
ALPHA_METHOD_SET,
ALPHA_METHOD_GREEN,
ALPHA_METHOD_BLUE,
ALPHA_METHOD_CUSTOM,
@ -64,6 +64,7 @@ struct _GstAlpha
/* caps */
gint in_width, in_height;
gint out_width, out_height;
gboolean ayuv;
gdouble alpha;
@ -107,7 +108,7 @@ enum
LAST_SIGNAL
};
#define DEFAULT_METHOD ALPHA_METHOD_ADD
#define DEFAULT_METHOD ALPHA_METHOD_SET
#define DEFAULT_ALPHA 1.0
#define DEFAULT_TARGET_R 0
#define DEFAULT_TARGET_G 255
@ -136,10 +137,12 @@ GST_STATIC_PAD_TEMPLATE ("src",
);
static GstStaticPadTemplate gst_alpha_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("I420"))
GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("AYUV")
";" GST_VIDEO_CAPS_YUV ("I420")
)
);
@ -168,7 +171,7 @@ gst_alpha_method_get_type (void)
{
static GType alpha_method_type = 0;
static GEnumValue alpha_method[] = {
{ALPHA_METHOD_ADD, "0", "Add alpha channel"},
{ALPHA_METHOD_SET, "0", "Set/adjust alpha channel"},
{ALPHA_METHOD_GREEN, "1", "Chroma Key green"},
{ALPHA_METHOD_BLUE, "2", "Chroma Key blue"},
{ALPHA_METHOD_CUSTOM, "3", "Chroma Key on target_r/g/b"},
@ -390,10 +393,26 @@ gst_alpha_sink_link (GstPad * pad, const GstCaps * caps)
GstAlpha *alpha;
GstStructure *structure;
gboolean ret;
guint32 fourcc;
alpha = GST_ALPHA (gst_pad_get_parent (pad));
structure = gst_caps_get_structure (caps, 0);
if (gst_structure_get_fourcc (structure, "format", &fourcc)) {
switch (fourcc) {
case GST_MAKE_FOURCC ('I', '4', '2', '0'):
alpha->ayuv = FALSE;
break;
case GST_MAKE_FOURCC ('A', 'Y', 'U', 'V'):
alpha->ayuv = TRUE;
break;
default:
return GST_PAD_LINK_REFUSED;
}
} else {
return GST_PAD_LINK_REFUSED;
}
ret = gst_structure_get_int (structure, "width", &alpha->in_width);
ret &= gst_structure_get_int (structure, "height", &alpha->in_height);
@ -401,7 +420,37 @@ gst_alpha_sink_link (GstPad * pad, const GstCaps * caps)
}
static void
gst_alpha_add (guint8 * src, guint8 * dest, gint width, gint height,
gst_alpha_set_ayuv (guint8 * src, guint8 * dest, gint width, gint height,
gdouble alpha)
{
gint b_alpha = (gint) (alpha * 255);
gint i, j;
gint size;
gint stride;
gint wrap;
width = ROUND_UP_2 (width);
height = ROUND_UP_2 (height);
stride = ROUND_UP_4 (width);
size = stride * height;
wrap = stride - width;
for (i = 0; i < height; i++) {
for (j = 0; j < width; j++) {
*dest++ = (*src++ * b_alpha) >> 8;
*dest++ = *src++;
*dest++ = *src++;
*dest++ = *src++;
}
src += wrap;
dest += wrap;
}
}
static void
gst_alpha_set_i420 (guint8 * src, guint8 * dest, gint width, gint height,
gdouble alpha)
{
gint b_alpha = (gint) (alpha * 255);
@ -450,18 +499,126 @@ gst_alpha_add (guint8 * src, guint8 * dest, gint width, gint height,
}
}
static void
gst_alpha_chroma_key_ayuv (gchar * src, gchar * dest, gint width, gint height,
GstAlpha * alpha)
{
gint b_alpha;
guint8 *src1;
guint8 *dest1;
gint i, j;
gint x, z, u, v, y, a;
gint size;
gint stride;
gint wrap;
gint tmp, tmp1;
gint x1, y1;
width = ROUND_UP_2 (width);
height = ROUND_UP_2 (height);
stride = ROUND_UP_4 (width);
size = stride * height;
src1 = src;
dest1 = dest;
wrap = stride - width;
for (i = 0; i < height; i++) {
for (j = 0; j < width; j++) {
a = *src1++ * (alpha->alpha);
y = *src1++;
u = *src1++ - 128;
v = *src1++ - 128;
/* Convert foreground to XZ coords where X direction is defined by
the key color */
tmp = ((short) u * alpha->cb + (short) v * alpha->cr) >> 7;
x = CLAMP (tmp, -128, 127);
tmp = ((short) v * alpha->cb - (short) u * alpha->cr) >> 7;
z = CLAMP (tmp, -128, 127);
/* WARNING: accept angle should never be set greater than "somewhat less
than 90 degrees" to avoid dealing with negative/infinite tg. In reality,
80 degrees should be enough if foreground is reasonable. If this seems
to be a problem, go to alternative ways of checking point position
(scalar product or line equations). This angle should not be too small
either to avoid infinite ctg (used to suppress foreground without use of
division) */
tmp = ((short) (x) * alpha->accept_angle_tg) >> 4;
tmp = MIN (tmp, 127);
if (abs (z) > tmp) {
/* keep foreground Kfg = 0 */
b_alpha = a;
} else {
/* Compute Kfg (implicitly) and Kbg, suppress foreground in XZ coord
according to Kfg */
tmp = ((short) (z) * alpha->accept_angle_ctg) >> 4;
tmp = CLAMP (tmp, -128, 127);
x1 = abs (tmp);
y1 = z;
tmp1 = x - x1;
tmp1 = MAX (tmp1, 0);
b_alpha = (((unsigned char) (tmp1) *
(unsigned short) (alpha->one_over_kc)) / 2);
b_alpha = 255 - CLAMP (b_alpha, 0, 255);
b_alpha = (a * b_alpha) >> 8;
tmp = ((unsigned short) (tmp1) * alpha->kfgy_scale) >> 4;
tmp1 = MIN (tmp, 255);
tmp = y - tmp1;
y = MAX (tmp, 0);
/* Convert suppressed foreground back to CbCr */
tmp = ((char) (x1) * (short) (alpha->cb) -
(char) (y1) * (short) (alpha->cr)) >> 7;
u = CLAMP (tmp, -128, 127);
tmp = ((char) (x1) * (short) (alpha->cr) +
(char) (y1) * (short) (alpha->cb)) >> 7;
v = CLAMP (tmp, -128, 127);
/* Deal with noise. For now, a circle around the key color with
radius of noise_level treated as exact key color. Introduces
sharp transitions.
*/
tmp = z * (short) (z) + (x - alpha->kg) * (short) (x - alpha->kg);
tmp = MIN (tmp, 0xffff);
if (tmp < alpha->noise_level * alpha->noise_level) {
b_alpha = 0;
}
}
u += 128;
v += 128;
*dest1++ = b_alpha;
*dest1++ = y;
*dest1++ = u;
*dest1++ = v;
}
dest1 += wrap;
src1 += wrap;
}
}
/* based on http://www.cs.utah.edu/~michael/chroma/
*/
static void
gst_alpha_chroma_key (gchar * src, gchar * dest, gint width, gint height,
gst_alpha_chroma_key_i420 (gchar * src, gchar * dest, gint width, gint height,
GstAlpha * alpha)
{
gint b_alpha;
guint8 *srcY1, *srcY2, *srcU, *srcV;
guint8 *dest1, *dest2;
gint i, j;
gint x, z, u, v, y11, y12, y21, y22;
gint x, z, u, v, y11, y12, y21, y22, a;
gint size, size2;
gint stride, stride2;
gint wrap, wrap2, wrap3;
@ -488,6 +645,8 @@ gst_alpha_chroma_key (gchar * src, gchar * dest, gint width, gint height,
wrap2 = stride2 - width / 2;
wrap3 = 8 * width - 8 * (width / 2);
a = 255 * alpha->alpha;
for (i = 0; i < height / 2; i++) {
for (j = 0; j < width / 2; j++) {
y11 = *srcY1++;
@ -531,6 +690,7 @@ gst_alpha_chroma_key (gchar * src, gchar * dest, gint width, gint height,
b_alpha = (((unsigned char) (tmp1) *
(unsigned short) (alpha->one_over_kc)) / 2);
b_alpha = 255 - CLAMP (b_alpha, 0, 255);
b_alpha = (a * b_alpha) >> 8;
tmp = ((unsigned short) (tmp1) * alpha->kfgy_scale) >> 4;
tmp1 = MIN (tmp, 255);
@ -682,21 +842,25 @@ gst_alpha_chain (GstPad * pad, GstData * _data)
GST_BUFFER_DURATION (outbuf) = GST_BUFFER_DURATION (buffer);
switch (alpha->method) {
case ALPHA_METHOD_ADD:
gst_alpha_add (GST_BUFFER_DATA (buffer),
GST_BUFFER_DATA (outbuf), new_width, new_height, alpha->alpha);
case ALPHA_METHOD_SET:
if (alpha->ayuv) {
gst_alpha_set_ayuv (GST_BUFFER_DATA (buffer),
GST_BUFFER_DATA (outbuf), new_width, new_height, alpha->alpha);
} else {
gst_alpha_set_i420 (GST_BUFFER_DATA (buffer),
GST_BUFFER_DATA (outbuf), new_width, new_height, alpha->alpha);
}
break;
case ALPHA_METHOD_GREEN:
gst_alpha_chroma_key (GST_BUFFER_DATA (buffer),
GST_BUFFER_DATA (outbuf), new_width, new_height, alpha);
break;
case ALPHA_METHOD_BLUE:
gst_alpha_chroma_key (GST_BUFFER_DATA (buffer),
GST_BUFFER_DATA (outbuf), new_width, new_height, alpha);
break;
case ALPHA_METHOD_CUSTOM:
gst_alpha_chroma_key (GST_BUFFER_DATA (buffer),
GST_BUFFER_DATA (outbuf), new_width, new_height, alpha);
if (alpha->ayuv) {
gst_alpha_chroma_key_ayuv (GST_BUFFER_DATA (buffer),
GST_BUFFER_DATA (outbuf), new_width, new_height, alpha);
} else {
gst_alpha_chroma_key_i420 (GST_BUFFER_DATA (buffer),
GST_BUFFER_DATA (outbuf), new_width, new_height, alpha);
}
break;
default:
break;