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gstreamer/ext/pango/gsttextoverlay.c
Iain Holmes a61b34b883 Text overlay 
Original commit message from CVS:
Text overlay
2003-11-02 01:21:38 +00:00

656 lines
19 KiB
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#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <gst/gst.h>
#include "gsttextoverlay.h"
/*#include "gsttexttestsrc.h"*/
/*#include "gstsubparse.h"*/
/*#include "SDL_blit.h"*/
static GstElementDetails textoverlay_details = {
"Text Overlay",
"Filter/Video",
"Adds text strings on top of a video buffer",
"Gustavo J. A. M. Carneiro <gjc@inescporto.pt>"
};
enum {
ARG_0,
ARG_TEXT,
ARG_VALIGN,
ARG_HALIGN,
ARG_X0,
ARG_Y0,
ARG_FONT_DESC,
};
GST_PAD_TEMPLATE_FACTORY(textoverlay_src_template_factory,
"src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_CAPS_NEW(
"textoverlay_src",
"video/x-raw-yuv",
"format", GST_PROPS_LIST(
GST_PROPS_FOURCC(GST_STR_FOURCC("I420"))
),
"width", GST_PROPS_INT_RANGE(0, G_MAXINT),
"height", GST_PROPS_INT_RANGE(0, G_MAXINT)
)
)
GST_PAD_TEMPLATE_FACTORY(video_sink_template_factory,
"video_sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_CAPS_NEW(
"video_sink",
"video/x-raw-yuv",
"format", GST_PROPS_LIST(
GST_PROPS_FOURCC(GST_STR_FOURCC("I420"))
),
"width", GST_PROPS_INT_RANGE(0, G_MAXINT),
"height", GST_PROPS_INT_RANGE(0, G_MAXINT)
)
)
GST_PAD_TEMPLATE_FACTORY(text_sink_template_factory,
"text_sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_CAPS_NEW(
"text_sink",
"text/x-pango-markup",
NULL
)
)
static void gst_textoverlay_base_init (gpointer g_class);
static void gst_textoverlay_class_init(GstTextOverlayClass *klass);
static void gst_textoverlay_init(GstTextOverlay *overlay);
static void gst_textoverlay_set_property(GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec);
static void gst_textoverlay_get_property(GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec);
static GstElementStateReturn gst_textoverlay_change_state(GstElement *element);
static void gst_textoverlay_finalize(GObject *object);
static GstElementClass *parent_class = NULL;
/*static guint gst_textoverlay_signals[LAST_SIGNAL] = { 0 }; */
GType
gst_textoverlay_get_type(void)
{
static GType textoverlay_type = 0;
if (!textoverlay_type) {
static const GTypeInfo textoverlay_info = {
sizeof(GstTextOverlayClass),
gst_textoverlay_base_init,
NULL,
(GClassInitFunc)gst_textoverlay_class_init,
NULL,
NULL,
sizeof(GstTextOverlay),
0,
(GInstanceInitFunc)gst_textoverlay_init,
};
textoverlay_type = g_type_register_static(GST_TYPE_ELEMENT, "GstTextOverlay",
&textoverlay_info, 0);
}
return textoverlay_type;
}
static void
gst_textoverlay_base_init (gpointer g_class)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_add_pad_template (element_class, GST_PAD_TEMPLATE_GET (textoverlay_src_template_factory));
gst_element_class_add_pad_template (element_class, GST_PAD_TEMPLATE_GET (video_sink_template_factory));
gst_element_class_add_pad_template (element_class, GST_PAD_TEMPLATE_GET (text_sink_template_factory));
gst_element_class_set_details (element_class, &textoverlay_details);
}
static void
gst_textoverlay_class_init(GstTextOverlayClass *klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass*)klass;
gstelement_class = (GstElementClass*)klass;
parent_class = g_type_class_peek_parent(klass);
gobject_class->finalize = gst_textoverlay_finalize;
gobject_class->set_property = gst_textoverlay_set_property;
gobject_class->get_property = gst_textoverlay_get_property;
gstelement_class->change_state = gst_textoverlay_change_state;
klass->pango_context = pango_ft2_get_context(72, 72);
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_TEXT,
g_param_spec_string("text", "text",
"Text to be display,"
" in pango markup format.",
"", G_PARAM_WRITABLE));
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_VALIGN,
g_param_spec_string("valign", "vertical alignment",
"Vertical alignment of the text. "
"Can be either 'baseline', 'bottom', or 'top'",
"baseline", G_PARAM_WRITABLE));
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_HALIGN,
g_param_spec_string("halign", "horizontal alignment",
"Horizontal alignment of the text. "
"Can be either 'left', 'right', or 'center'",
"center", G_PARAM_WRITABLE));
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_X0,
g_param_spec_int("x0", "X position",
"Initial X position."
" Horizontal aligment takes this point"
" as reference.",
G_MININT, G_MAXINT, 0, G_PARAM_WRITABLE));
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_Y0,
g_param_spec_int("y0", "Y position",
"Initial Y position."
" Vertical aligment takes this point"
" as reference.",
G_MININT, G_MAXINT, 0, G_PARAM_WRITABLE));
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_FONT_DESC,
g_param_spec_string("font-desc", "font description",
"Pango font description of font "
"to be used for rendering. "
"See documentation of "
"pango_font_description_from_string"
" for syntax.",
"", G_PARAM_WRITABLE));
}
static void
resize_bitmap(GstTextOverlay *overlay, int width, int height)
{
FT_Bitmap *bitmap = &overlay->bitmap;
int pitch = (width|3) + 1;
int size = pitch*height;
/* no need to keep reallocating; just keep the maximum size so far */
if (size <= overlay->bitmap_buffer_size) {
bitmap->rows = height;
bitmap->width = width;
bitmap->pitch = pitch;
memset(bitmap->buffer, 0, overlay->bitmap_buffer_size);
return;
}
if (!bitmap->buffer) {
/* initialize */
bitmap->pixel_mode = ft_pixel_mode_grays;
bitmap->num_grays = 256;
}
if (bitmap->buffer)
bitmap->buffer = g_realloc(bitmap->buffer, size);
else
bitmap->buffer = g_malloc(size);
bitmap->rows = height;
bitmap->width = width;
bitmap->pitch = pitch;
memset(bitmap->buffer, 0, size);
overlay->bitmap_buffer_size = size;
}
static void
render_text(GstTextOverlay *overlay)
{
PangoRectangle ink_rect, logical_rect;
pango_layout_get_pixel_extents(overlay->layout, &ink_rect, &logical_rect);
resize_bitmap(overlay, ink_rect.width, ink_rect.height + ink_rect.y);
pango_ft2_render_layout(&overlay->bitmap, overlay->layout, 0, 0);
overlay->baseline_y = ink_rect.y;
}
/* static GstPadLinkReturn */
/* gst_textoverlay_text_sinkconnect (GstPad *pad, GstCaps *caps) */
/* { */
/* return GST_PAD_LINK_DONE; */
/* } */
static GstPadLinkReturn
gst_textoverlay_video_sinkconnect(GstPad *pad, GstCaps *caps)
{
GstTextOverlay *overlay;
overlay = GST_TEXTOVERLAY(gst_pad_get_parent(pad));
if (!GST_CAPS_IS_FIXED(caps))
return GST_PAD_LINK_DELAYED;
overlay->width = overlay->height = 0;
gst_caps_get_int(caps, "width", &overlay->width);
gst_caps_get_int(caps, "height", &overlay->height);
return gst_pad_try_set_caps(overlay->srcpad, caps);
}
static void
gst_text_overlay_blit_yuv420(GstTextOverlay *overlay, FT_Bitmap *bitmap,
guchar *pixbuf, int x0, int y0)
{
int y; /* text bitmap coordinates */
int x1, y1; /* video buffer coordinates */
int rowinc, bit_rowinc, uv_rowinc;
guchar *p, *bitp, *u_p;
int video_width = overlay->width, video_height = overlay->height;
int bitmap_x0 = x0 < 1? -(x0 - 1) : 1; /* 1 pixel border */
int bitmap_y0 = y0 < 1? -(y0 - 1) : 1; /* 1 pixel border */
int bitmap_width = bitmap->width - bitmap_x0;
int bitmap_height = bitmap->rows - bitmap_y0;
int u_plane_size;
int skip_y, skip_x;
guchar v;
if (x0 + bitmap_x0 + bitmap_width > video_width - 1) /* 1 pixel border */
bitmap_width -= x0 + bitmap_x0 + bitmap_width - video_width + 1;
if (y0 + bitmap_y0 + bitmap_height > video_height - 1) /* 1 pixel border */
bitmap_height -= y0 + bitmap_y0 + bitmap_height - video_height + 1;
rowinc = video_width - bitmap_width;
uv_rowinc = video_width / 2 - bitmap_width / 2;
bit_rowinc = bitmap->pitch - bitmap_width;
u_plane_size = (video_width / 2)*(video_height / 2);
y1 = y0 + bitmap_y0;
x1 = x0 + bitmap_x0;
p = pixbuf + video_width*y1 + x1;
bitp = bitmap->buffer + bitmap->pitch*bitmap_y0 + bitmap_x0;
for (y = bitmap_y0; y < bitmap_height; y++){
int n;
for(n=bitmap_width; n>0; --n){
v = *bitp;
if (v) {
p[-1] = CLAMP(p[-1] - v, 0, 255);
p[ 1] = CLAMP(p[ 1] - v, 0, 255);
p[-video_width] = CLAMP(p[-video_width] - v, 0, 255);
p[ video_width] = CLAMP(p[ video_width] - v, 0, 255);
}
p++;
bitp++;
}
p += rowinc;
bitp += bit_rowinc;
}
y = bitmap_y0;
y1 = y0 + bitmap_y0;
x1 = x0 + bitmap_x0;
bitp = bitmap->buffer + bitmap->pitch*bitmap_y0 + bitmap_x0;
p = pixbuf + video_width*y1 + x1;
u_p = pixbuf + video_width*video_height + (video_width >> 1)*(y1 >> 1) + (x1 >> 1);
skip_y = 0;
skip_x = 0;
for ( ; y < bitmap_height; y++){
int n;
x1 = x0 + bitmap_x0;
skip_x = 0;
for(n = bitmap_width; n>0; --n){
v = *bitp;
if (v) {
*p = v;
if (!skip_y) {
u_p[0] = u_p[u_plane_size] = 0x80;
}
}
if (!skip_y) {
skip_x = !skip_x;
if (!skip_x) u_p++;
}
p++;
bitp++;
}
/*if (!skip_x && !skip_y) u_p--; */
p += rowinc;
bitp += bit_rowinc;
skip_y = !skip_y;
u_p += skip_y? uv_rowinc : 0;
}
}
static void
gst_textoverlay_video_chain(GstPad *pad, GstData *_data)
{
GstBuffer *buf = GST_BUFFER (_data);
GstTextOverlay *overlay;
guchar *pixbuf;
gint x0, y0;
g_return_if_fail(pad != NULL);
g_return_if_fail(GST_IS_PAD(pad));
g_return_if_fail(buf != NULL);
overlay = GST_TEXTOVERLAY(gst_pad_get_parent(pad));
g_return_if_fail(overlay != NULL);
g_return_if_fail(GST_IS_TEXTOVERLAY(overlay));
pixbuf = GST_BUFFER_DATA(buf);
x0 = overlay->x0;
y0 = overlay->y0;
switch (overlay->valign)
{
case GST_TEXT_OVERLAY_VALIGN_BOTTOM:
y0 += overlay->bitmap.rows;
break;
case GST_TEXT_OVERLAY_VALIGN_BASELINE:
y0 -= (overlay->bitmap.rows - overlay->baseline_y);
break;
case GST_TEXT_OVERLAY_VALIGN_TOP:
break;
}
switch (overlay->halign)
{
case GST_TEXT_OVERLAY_HALIGN_LEFT:
break;
case GST_TEXT_OVERLAY_HALIGN_RIGHT:
x0 -= overlay->bitmap.width;
break;
case GST_TEXT_OVERLAY_HALIGN_CENTER:
x0 -= overlay->bitmap.width / 2;
break;
}
if (overlay->bitmap.buffer)
gst_text_overlay_blit_yuv420(overlay, &overlay->bitmap, pixbuf, x0, y0);
gst_pad_push(overlay->srcpad, GST_DATA (buf));
}
#define PAST_END(buffer, time) \
(GST_BUFFER_TIMESTAMP (buffer) != GST_CLOCK_TIME_NONE && \
GST_BUFFER_DURATION (buffer) != GST_CLOCK_TIME_NONE && \
GST_BUFFER_TIMESTAMP (buffer) + GST_BUFFER_DURATION (buffer) \
< (time))
static void
gst_textoverlay_loop(GstElement *element)
{
GstTextOverlay *overlay;
GstBuffer *video_frame;
guint64 now;
g_return_if_fail(element != NULL);
g_return_if_fail(GST_IS_TEXTOVERLAY(element));
overlay = GST_TEXTOVERLAY(element);
video_frame = GST_BUFFER (gst_pad_pull(overlay->video_sinkpad));
now = GST_BUFFER_TIMESTAMP(video_frame);
/*
* This state machine has a bug that can't be resolved easily.
* (Needs a more complicated state machine.) Basically, if the
* text that came from a buffer from the sink pad is being
* displayed, and the default text is changed by set_parameter,
* we'll incorrectly display the default text.
*
* Otherwise, this is a pretty decent state machine that handles
* buffer timestamps and durations correctly. (I think)
*/
while (overlay->next_buffer == NULL){
GST_DEBUG("attempting to pull a buffer");
/* read all text buffers until we get one "in the future" */
if(!GST_PAD_IS_USABLE(overlay->text_sinkpad)){
break;
}
overlay->next_buffer = GST_BUFFER (gst_pad_pull(overlay->text_sinkpad));
if (!overlay->next_buffer)
break;
if (PAST_END(overlay->next_buffer, now)){
gst_buffer_unref(overlay->next_buffer);
overlay->next_buffer = NULL;
}
}
if (overlay->next_buffer &&
(GST_BUFFER_TIMESTAMP(overlay->next_buffer) <= now ||
GST_BUFFER_TIMESTAMP(overlay->next_buffer) == GST_CLOCK_TIME_NONE)){
GST_DEBUG("using new buffer");
if (overlay->current_buffer){
gst_buffer_unref (overlay->current_buffer);
}
overlay->current_buffer = overlay->next_buffer;
overlay->next_buffer = NULL;
GST_DEBUG ( "rendering '%*s'",
GST_BUFFER_SIZE(overlay->current_buffer),
GST_BUFFER_DATA(overlay->current_buffer));
pango_layout_set_markup(overlay->layout,
GST_BUFFER_DATA(overlay->current_buffer),
GST_BUFFER_SIZE(overlay->current_buffer));
render_text(overlay);
overlay->need_render = FALSE;
}
if (overlay->current_buffer && PAST_END(overlay->current_buffer, now)){
GST_DEBUG("dropping old buffer");
gst_buffer_unref(overlay->current_buffer);
overlay->current_buffer = NULL;
overlay->need_render = TRUE;
}
if(overlay->need_render){
GST_DEBUG ( "rendering '%s'", overlay->default_text);
pango_layout_set_markup(overlay->layout,
overlay->default_text, strlen(overlay->default_text));
render_text(overlay);
overlay->need_render = FALSE;
}
gst_textoverlay_video_chain(overlay->srcpad, GST_DATA (video_frame));
}
static GstElementStateReturn
gst_textoverlay_change_state(GstElement *element)
{
GstTextOverlay *overlay;
overlay = GST_TEXTOVERLAY(element);
switch (GST_STATE_TRANSITION(element))
{
case GST_STATE_PAUSED_TO_PLAYING:
break;
case GST_STATE_PLAYING_TO_PAUSED:
break;
case GST_STATE_PAUSED_TO_READY:
break;
}
parent_class->change_state(element);
return GST_STATE_SUCCESS;
}
static void
gst_textoverlay_finalize(GObject *object)
{
GstTextOverlay *overlay = GST_TEXTOVERLAY(object);
if (overlay->layout) {
g_object_unref(overlay->layout);
overlay->layout = NULL;
}
if (overlay->bitmap.buffer) {
g_free(overlay->bitmap.buffer);
overlay->bitmap.buffer = NULL;
}
G_OBJECT_CLASS(parent_class)->finalize(object);
}
static void
gst_textoverlay_init(GstTextOverlay *overlay)
{
/* video sink */
overlay->video_sinkpad = gst_pad_new_from_template(
GST_PAD_TEMPLATE_GET(video_sink_template_factory), "video_sink");
/* gst_pad_set_chain_function(overlay->video_sinkpad, gst_textoverlay_video_chain); */
gst_pad_set_link_function(overlay->video_sinkpad, gst_textoverlay_video_sinkconnect);
gst_element_add_pad(GST_ELEMENT(overlay), overlay->video_sinkpad);
/* text sink */
overlay->text_sinkpad = gst_pad_new_from_template(
GST_PAD_TEMPLATE_GET(text_sink_template_factory), "text_sink");
/* gst_pad_set_link_function(overlay->text_sinkpad, gst_textoverlay_text_sinkconnect); */
gst_element_add_pad(GST_ELEMENT(overlay), overlay->text_sinkpad);
/* (video) source */
overlay->srcpad = gst_pad_new_from_template(
GST_PAD_TEMPLATE_GET(textoverlay_src_template_factory), "src");
gst_element_add_pad(GST_ELEMENT(overlay), overlay->srcpad);
overlay->layout = pango_layout_new(GST_TEXTOVERLAY_GET_CLASS(overlay)->pango_context);
memset(&overlay->bitmap, 0, sizeof(overlay->bitmap));
overlay->halign = GST_TEXT_OVERLAY_HALIGN_CENTER;
overlay->valign = GST_TEXT_OVERLAY_VALIGN_BASELINE;
overlay->x0 = overlay->y0 = 0;
overlay->default_text = g_strdup("");
overlay->need_render = TRUE;
gst_element_set_loop_function(GST_ELEMENT(overlay), gst_textoverlay_loop);
}
static void
gst_textoverlay_set_property(GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
{
GstTextOverlay *overlay;
/* it's not null if we got it, but it might not be ours */
g_return_if_fail(GST_IS_TEXTOVERLAY(object));
overlay = GST_TEXTOVERLAY(object);
switch (prop_id)
{
case ARG_TEXT:
if(overlay->default_text){
g_free(overlay->default_text);
}
overlay->default_text = g_strdup(g_value_get_string(value));
overlay->need_render = TRUE;
break;
case ARG_VALIGN:
if (strcasecmp(g_value_get_string(value), "baseline") == 0)
overlay->valign = GST_TEXT_OVERLAY_VALIGN_BASELINE;
else if (strcasecmp(g_value_get_string(value), "bottom") == 0)
overlay->valign = GST_TEXT_OVERLAY_VALIGN_BOTTOM;
else if (strcasecmp(g_value_get_string(value), "top") == 0)
overlay->valign = GST_TEXT_OVERLAY_VALIGN_TOP;
else
g_warning("Invalid 'valign' property value: %s",
g_value_get_string(value));
break;
case ARG_HALIGN:
if (strcasecmp(g_value_get_string(value), "left") == 0)
overlay->halign = GST_TEXT_OVERLAY_HALIGN_LEFT;
else if (strcasecmp(g_value_get_string(value), "right") == 0)
overlay->halign = GST_TEXT_OVERLAY_HALIGN_RIGHT;
else if (strcasecmp(g_value_get_string(value), "center") == 0)
overlay->halign = GST_TEXT_OVERLAY_HALIGN_CENTER;
else
g_warning("Invalid 'halign' property value: %s",
g_value_get_string(value));
break;
case ARG_X0:
overlay->x0 = g_value_get_int(value);
break;
case ARG_Y0:
overlay->y0 = g_value_get_int(value);
break;
case ARG_FONT_DESC:
{
PangoFontDescription *desc;
desc = pango_font_description_from_string(g_value_get_string(value));
if (desc) {
g_message("font description set: %s", g_value_get_string(value));
pango_layout_set_font_description(overlay->layout, desc);
pango_font_description_free(desc);
render_text(overlay);
} else
g_warning("font description parse failed: %s", g_value_get_string(value));
break;
}
default:
break;
}
}
static void
gst_textoverlay_get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
{
GstTextOverlay *overlay;
/* it's not null if we got it, but it might not be ours */
g_return_if_fail(GST_IS_TEXTOVERLAY(object));
overlay = GST_TEXTOVERLAY(object);
switch (prop_id) {
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
break;
}
}
static gboolean
plugin_init(GstPlugin *plugin)
{
if (!gst_element_register (plugin, "textoverlay", GST_RANK_PRIMARY, GST_TYPE_TEXTOVERLAY))
return FALSE;
/*texttestsrc_plugin_init(module, plugin);*/
/*subparse_plugin_init(module, plugin);*/
return TRUE;
}
GST_PLUGIN_DEFINE (
GST_VERSION_MAJOR,
GST_VERSION_MINOR,
"textoverlay",
"Text overlay",
plugin_init,
VERSION,
"GPL",
GST_COPYRIGHT,
GST_PACKAGE,
GST_ORIGIN)
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