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GST-Tensordecoder-ov_ep/subprojects/gst-plugins-bad/gst/ivtc/gstivtc.c

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/* GStreamer
* Copyright (C) 2013 David Schleef <ds@schleef.org>
* Copyright (C) 2013 Rdio Inc <ingestions@rdio.com>
*
* 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., 51 Franklin Street, Suite 500,
* Boston, MA 02110-1335, USA.
*/
/**
* SECTION:element-ivtc
* @title: gstivtc
*
* The ivtc element is an inverse telecine filter. It takes interlaced
* video that was created from progressive content using a telecine
* filter, and reconstructs the original progressive content.
*
* ## Example launch line
* |[
* gst-launch-1.0 -v videotestsrc pattern=ball ! video/x-raw,framerate=24/1 !
* interlace !
* ivtc ! video/x-raw,framerate=24/1 ! fakesink
* ]|
*
* This pipeline creates a progressive video stream at 24 fps, and
* converts it to a 60 fields per second interlaced stream. Then the
* stream is inversed telecine'd back to 24 fps, yielding approximately
* the original videotestsrc content.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include <gst/base/gstbasetransform.h>
#include <gst/video/video.h>
#include "gstivtc.h"
#include <string.h>
#include <math.h>
/* only because element registration is in this file */
#include "gstcombdetect.h"
GST_DEBUG_CATEGORY_STATIC (gst_ivtc_debug_category);
#define GST_CAT_DEFAULT gst_ivtc_debug_category
/* prototypes */
static GstCaps *gst_ivtc_transform_caps (GstBaseTransform * trans,
GstPadDirection direction, GstCaps * caps, GstCaps * filter);
static GstCaps *gst_ivtc_fixate_caps (GstBaseTransform * trans,
GstPadDirection direction, GstCaps * caps, GstCaps * othercaps);
static gboolean gst_ivtc_set_caps (GstBaseTransform * trans, GstCaps * incaps,
GstCaps * outcaps);
static gboolean gst_ivtc_sink_event (GstBaseTransform * trans,
GstEvent * event);
static GstFlowReturn gst_ivtc_transform (GstBaseTransform * trans,
GstBuffer * inbuf, GstBuffer * outbuf);
static void gst_ivtc_flush (GstIvtc * ivtc);
static void gst_ivtc_retire_fields (GstIvtc * ivtc, int n_fields);
static void gst_ivtc_construct_frame (GstIvtc * itvc, GstBuffer * outbuf);
static int get_comb_score (GstVideoFrame * top, GstVideoFrame * bottom);
enum
{
PROP_0
};
/* pad templates */
#define MAX_WIDTH 2048
#define VIDEO_CAPS \
"video/x-raw, " \
"format = (string) { I420, Y444, Y42B }, " \
"width = [1, 2048], " \
"height = " GST_VIDEO_SIZE_RANGE ", " \
"framerate = " GST_VIDEO_FPS_RANGE
static GstStaticPadTemplate gst_ivtc_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (VIDEO_CAPS)
);
static GstStaticPadTemplate gst_ivtc_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (VIDEO_CAPS)
);
/* class initialization */
G_DEFINE_TYPE_WITH_CODE (GstIvtc, gst_ivtc, GST_TYPE_BASE_TRANSFORM,
GST_DEBUG_CATEGORY_INIT (gst_ivtc_debug_category, "ivtc", 0,
"debug category for ivtc element"));
GST_ELEMENT_REGISTER_DEFINE (ivtc, "ivtc", GST_RANK_NONE, GST_TYPE_IVTC);
static void
gst_ivtc_class_init (GstIvtcClass * klass)
{
GstBaseTransformClass *base_transform_class =
GST_BASE_TRANSFORM_CLASS (klass);
/* Setting up pads and setting metadata should be moved to
base_class_init if you intend to subclass this class. */
gst_element_class_add_static_pad_template (GST_ELEMENT_CLASS (klass),
&gst_ivtc_sink_template);
gst_element_class_add_static_pad_template (GST_ELEMENT_CLASS (klass),
&gst_ivtc_src_template);
gst_element_class_set_static_metadata (GST_ELEMENT_CLASS (klass),
"Inverse Telecine", "Video/Filter", "Inverse Telecine Filter",
"David Schleef <ds@schleef.org>");
base_transform_class->transform_caps =
GST_DEBUG_FUNCPTR (gst_ivtc_transform_caps);
base_transform_class->fixate_caps = GST_DEBUG_FUNCPTR (gst_ivtc_fixate_caps);
base_transform_class->set_caps = GST_DEBUG_FUNCPTR (gst_ivtc_set_caps);
base_transform_class->sink_event = GST_DEBUG_FUNCPTR (gst_ivtc_sink_event);
base_transform_class->transform = GST_DEBUG_FUNCPTR (gst_ivtc_transform);
}
static void
gst_ivtc_init (GstIvtc * ivtc)
{
}
static GstCaps *
gst_ivtc_transform_caps (GstBaseTransform * trans,
GstPadDirection direction, GstCaps * caps, GstCaps * filter)
{
GstCaps *othercaps;
int i;
othercaps = gst_caps_copy (caps);
if (direction == GST_PAD_SRC) {
GValue value = G_VALUE_INIT;
GValue v = G_VALUE_INIT;
g_value_init (&value, GST_TYPE_LIST);
g_value_init (&v, G_TYPE_STRING);
g_value_set_string (&v, "interleaved");
gst_value_list_append_value (&value, &v);
g_value_set_string (&v, "mixed");
gst_value_list_append_value (&value, &v);
g_value_set_string (&v, "progressive");
gst_value_list_append_value (&value, &v);
for (i = 0; i < gst_caps_get_size (othercaps); i++) {
GstStructure *structure = gst_caps_get_structure (othercaps, i);
gst_structure_set_value (structure, "interlace-mode", &value);
gst_structure_remove_field (structure, "framerate");
}
g_value_unset (&value);
g_value_unset (&v);
} else {
for (i = 0; i < gst_caps_get_size (othercaps); i++) {
GstStructure *structure = gst_caps_get_structure (othercaps, i);
gst_structure_set (structure, "interlace-mode", G_TYPE_STRING,
"progressive", NULL);
gst_structure_remove_field (structure, "framerate");
}
}
if (filter) {
GstCaps *intersect;
intersect = gst_caps_intersect (othercaps, filter);
gst_caps_unref (othercaps);
othercaps = intersect;
}
return othercaps;
}
static GstCaps *
gst_ivtc_fixate_caps (GstBaseTransform * trans, GstPadDirection direction,
GstCaps * caps, GstCaps * othercaps)
{
GstCaps *result;
GST_DEBUG_OBJECT (trans, "fixating caps %" GST_PTR_FORMAT, othercaps);
result = gst_caps_make_writable (othercaps);
if (direction == GST_PAD_SINK) {
GstVideoInfo info;
if (gst_video_info_from_caps (&info, caps)) {
/* Smarter decision */
GST_DEBUG_OBJECT (trans, "Input framerate is %d/%d", info.fps_n,
info.fps_d);
if (info.fps_n == 30000 && info.fps_d == 1001)
gst_caps_set_simple (result, "framerate", GST_TYPE_FRACTION, 24000,
1001, NULL);
else
gst_caps_set_simple (result, "framerate", GST_TYPE_FRACTION, 24, 1,
NULL);
} else {
gst_caps_set_simple (result, "framerate", GST_TYPE_FRACTION, 24, 1, NULL);
}
}
result = gst_caps_fixate (result);
return result;
}
static gboolean
gst_ivtc_set_caps (GstBaseTransform * trans, GstCaps * incaps,
GstCaps * outcaps)
{
GstIvtc *ivtc = GST_IVTC (trans);
gst_video_info_from_caps (&ivtc->sink_video_info, incaps);
gst_video_info_from_caps (&ivtc->src_video_info, outcaps);
ivtc->field_duration = gst_util_uint64_scale_int (GST_SECOND,
ivtc->sink_video_info.fps_d, ivtc->sink_video_info.fps_n * 2);
GST_DEBUG_OBJECT (trans, "field duration %" GST_TIME_FORMAT,
GST_TIME_ARGS (ivtc->field_duration));
return TRUE;
}
/* sink and src pad event handlers */
static gboolean
gst_ivtc_sink_event (GstBaseTransform * trans, GstEvent * event)
{
GstIvtc *ivtc = GST_IVTC (trans);
GST_DEBUG_OBJECT (ivtc, "sink_event");
if (GST_EVENT_TYPE (event) == GST_EVENT_SEGMENT) {
const GstSegment *seg;
gst_ivtc_flush (ivtc);
/* FIXME this should handle update events */
gst_event_parse_segment (event, &seg);
gst_segment_copy_into (seg, &ivtc->segment);
ivtc->current_ts = ivtc->segment.start;
}
return GST_BASE_TRANSFORM_CLASS (gst_ivtc_parent_class)->sink_event (trans,
event);
}
static void
gst_ivtc_flush (GstIvtc * ivtc)
{
if (ivtc->n_fields > 0) {
GST_FIXME_OBJECT (ivtc, "not sending flushed fields to srcpad");
}
gst_ivtc_retire_fields (ivtc, ivtc->n_fields);
}
enum
{
TOP_FIELD = 0,
BOTTOM_FIELD = 1
};
static void
add_field (GstIvtc * ivtc, GstBuffer * buffer, int parity, int index)
{
int i = ivtc->n_fields;
GstClockTime ts;
GstIvtcField *field = &ivtc->fields[i];
g_return_if_fail (i < GST_IVTC_MAX_FIELDS);
ts = GST_BUFFER_PTS (buffer) + index * ivtc->field_duration;
if (ts + ivtc->field_duration < ivtc->segment.start) {
/* drop, it's before our segment */
return;
}
GST_DEBUG ("adding field %d", i);
field->buffer = gst_buffer_ref (buffer);
field->parity = parity;
field->ts = ts;
gst_video_frame_map (&ivtc->fields[i].frame, &ivtc->sink_video_info,
buffer, GST_MAP_READ);
ivtc->n_fields++;
}
static int
similarity (GstIvtc * ivtc, int i1, int i2)
{
GstIvtcField *f1, *f2;
int score;
g_return_val_if_fail (i1 >= 0 && i1 < ivtc->n_fields, 0);
g_return_val_if_fail (i2 >= 0 && i2 < ivtc->n_fields, 0);
f1 = &ivtc->fields[i1];
f2 = &ivtc->fields[i2];
if (f1->parity == TOP_FIELD) {
score = get_comb_score (&f1->frame, &f2->frame);
} else {
score = get_comb_score (&f2->frame, &f1->frame);
}
GST_DEBUG ("score %d", score);
return score;
}
#define GET_LINE(frame,comp,line) (((unsigned char *)(frame)->data[k]) + \
(line) * GST_VIDEO_FRAME_COMP_STRIDE((frame), (comp)))
#define GET_LINE_IL(top,bottom,comp,line) \
(((unsigned char *)(((line)&1)?(bottom):(top))->data[k]) + \
(line) * GST_VIDEO_FRAME_COMP_STRIDE((top), (comp)))
static void
reconstruct (GstIvtc * ivtc, GstVideoFrame * dest_frame, int i1, int i2)
{
GstVideoFrame *top, *bottom;
int width, height;
int j, k;
g_return_if_fail (i1 >= 0 && i1 < ivtc->n_fields);
g_return_if_fail (i2 >= 0 && i2 < ivtc->n_fields);
if (ivtc->fields[i1].parity == TOP_FIELD) {
top = &ivtc->fields[i1].frame;
bottom = &ivtc->fields[i2].frame;
} else {
bottom = &ivtc->fields[i1].frame;
top = &ivtc->fields[i2].frame;
}
for (k = 0; k < 3; k++) {
height = GST_VIDEO_FRAME_COMP_HEIGHT (top, k);
width = GST_VIDEO_FRAME_COMP_WIDTH (top, k);
for (j = 0; j < height; j++) {
guint8 *dest = GET_LINE (dest_frame, k, j);
guint8 *src = GET_LINE_IL (top, bottom, k, j);
memcpy (dest, src, width);
}
}
}
static int
reconstruct_line (guint8 * line1, guint8 * line2, int i, int a, int b, int c,
int d)
{
int x;
x = line1[i - 3] * a;
x += line1[i - 2] * b;
x += line1[i - 1] * c;
x += line1[i - 0] * d;
x += line2[i + 0] * d;
x += line2[i + 1] * c;
x += line2[i + 2] * b;
x += line2[i + 3] * a;
return (x + 16) >> 5;
}
static void
reconstruct_single (GstIvtc * ivtc, GstVideoFrame * dest_frame, int i1)
{
int j;
int k;
int height;
int width;
GstIvtcField *field = &ivtc->fields[i1];
for (k = 0; k < 1; k++) {
height = GST_VIDEO_FRAME_COMP_HEIGHT (dest_frame, k);
width = GST_VIDEO_FRAME_COMP_WIDTH (dest_frame, k);
for (j = 0; j < height; j++) {
if ((j & 1) == field->parity) {
memcpy (GET_LINE (dest_frame, k, j),
GET_LINE (&field->frame, k, j), width);
} else {
if (j == 0 || j == height - 1) {
memcpy (GET_LINE (dest_frame, k, j),
GET_LINE (&field->frame, k, (j ^ 1)), width);
} else {
guint8 *dest = GET_LINE (dest_frame, k, j);
guint8 *line1 = GET_LINE (&field->frame, k, j - 1);
guint8 *line2 = GET_LINE (&field->frame, k, j + 1);
int i;
#define MARGIN 3
for (i = MARGIN; i < width - MARGIN; i++) {
int dx, dy;
dx = -line1[i - 1] - line2[i - 1] + line1[i + 1] + line2[i + 1];
dx *= 2;
dy = -line1[i - 1] - 2 * line1[i] - line1[i + 1]
+ line2[i - 1] + 2 * line2[i] + line2[i + 1];
if (dy < 0) {
dy = -dy;
dx = -dx;
}
if (dx == 0 && dy == 0) {
dest[i] = (line1[i] + line2[i] + 1) >> 1;
} else if (dx < 0) {
if (dx < -2 * dy) {
dest[i] = reconstruct_line (line1, line2, i, 0, 0, 0, 16);
} else if (dx < -dy) {
dest[i] = reconstruct_line (line1, line2, i, 0, 0, 8, 8);
} else if (2 * dx < -dy) {
dest[i] = reconstruct_line (line1, line2, i, 0, 4, 8, 4);
} else if (3 * dx < -dy) {
dest[i] = reconstruct_line (line1, line2, i, 1, 7, 7, 1);
} else {
dest[i] = reconstruct_line (line1, line2, i, 4, 8, 4, 0);
}
} else {
if (dx > 2 * dy) {
dest[i] = reconstruct_line (line2, line1, i, 0, 0, 0, 16);
} else if (dx > dy) {
dest[i] = reconstruct_line (line2, line1, i, 0, 0, 8, 8);
} else if (2 * dx > dy) {
dest[i] = reconstruct_line (line2, line1, i, 0, 4, 8, 4);
} else if (3 * dx > dy) {
dest[i] = reconstruct_line (line2, line1, i, 1, 7, 7, 1);
} else {
dest[i] = reconstruct_line (line2, line1, i, 4, 8, 4, 0);
}
}
}
for (i = 0; i < MARGIN; i++) {
dest[i] = (line1[i] + line2[i] + 1) >> 1;
}
for (i = width - MARGIN; i < width; i++) {
dest[i] = (line1[i] + line2[i] + 1) >> 1;
}
}
}
}
}
for (k = 1; k < 3; k++) {
height = GST_VIDEO_FRAME_COMP_HEIGHT (dest_frame, k);
width = GST_VIDEO_FRAME_COMP_WIDTH (dest_frame, k);
for (j = 0; j < height; j++) {
if ((j & 1) == field->parity) {
memcpy (GET_LINE (dest_frame, k, j),
GET_LINE (&field->frame, k, j), width);
} else {
if (j == 0 || j == height - 1) {
memcpy (GET_LINE (dest_frame, k, j),
GET_LINE (&field->frame, k, (j ^ 1)), width);
} else {
guint8 *dest = GET_LINE (dest_frame, k, j);
guint8 *line1 = GET_LINE (&field->frame, k, j - 1);
guint8 *line2 = GET_LINE (&field->frame, k, j + 1);
int i;
for (i = 0; i < width; i++) {
dest[i] = (line1[i] + line2[i] + 1) >> 1;
}
}
}
}
}
}
static void
gst_ivtc_retire_fields (GstIvtc * ivtc, int n_fields)
{
int i;
if (n_fields == 0)
return;
for (i = 0; i < n_fields; i++) {
gst_video_frame_unmap (&ivtc->fields[i].frame);
gst_buffer_unref (ivtc->fields[i].buffer);
}
memmove (ivtc->fields, ivtc->fields + n_fields,
sizeof (GstIvtcField) * (ivtc->n_fields - n_fields));
ivtc->n_fields -= n_fields;
}
static GstFlowReturn
gst_ivtc_transform (GstBaseTransform * trans, GstBuffer * inbuf,
GstBuffer * outbuf)
{
GstIvtc *ivtc = GST_IVTC (trans);
GstFlowReturn ret;
GST_DEBUG_OBJECT (ivtc, "transform");
if (GST_BUFFER_FLAG_IS_SET (inbuf, GST_VIDEO_BUFFER_FLAG_TFF)) {
add_field (ivtc, inbuf, TOP_FIELD, 0);
if (!GST_BUFFER_FLAG_IS_SET (inbuf, GST_VIDEO_BUFFER_FLAG_ONEFIELD)) {
add_field (ivtc, inbuf, BOTTOM_FIELD, 1);
if (GST_BUFFER_FLAG_IS_SET (inbuf, GST_VIDEO_BUFFER_FLAG_RFF)) {
add_field (ivtc, inbuf, TOP_FIELD, 2);
}
}
} else {
add_field (ivtc, inbuf, BOTTOM_FIELD, 0);
if (!GST_BUFFER_FLAG_IS_SET (inbuf, GST_VIDEO_BUFFER_FLAG_ONEFIELD)) {
add_field (ivtc, inbuf, TOP_FIELD, 1);
if (GST_BUFFER_FLAG_IS_SET (inbuf, GST_VIDEO_BUFFER_FLAG_RFF)) {
add_field (ivtc, inbuf, BOTTOM_FIELD, 2);
}
}
}
while (ivtc->n_fields > 0 &&
ivtc->fields[0].ts + GST_MSECOND * 50 < ivtc->current_ts) {
GST_DEBUG ("retiring early field");
gst_ivtc_retire_fields (ivtc, 1);
}
GST_DEBUG ("n_fields %d", ivtc->n_fields);
if (ivtc->n_fields < 4) {
return GST_BASE_TRANSFORM_FLOW_DROPPED;
}
gst_ivtc_construct_frame (ivtc, outbuf);
while (ivtc->n_fields >= 4) {
GstBuffer *buf;
buf = gst_buffer_copy (outbuf);
GST_DEBUG ("pushing extra frame");
ret = gst_pad_push (GST_BASE_TRANSFORM_SRC_PAD (trans), buf);
if (ret != GST_FLOW_OK) {
return ret;
}
gst_ivtc_construct_frame (ivtc, outbuf);
}
return GST_FLOW_OK;
}
static void
gst_ivtc_construct_frame (GstIvtc * ivtc, GstBuffer * outbuf)
{
int anchor_index;
int prev_score, next_score;
GstVideoFrame dest_frame;
int n_retire;
gboolean forward_ok;
anchor_index = 1;
if (ivtc->fields[anchor_index].ts < ivtc->current_ts) {
forward_ok = TRUE;
} else {
forward_ok = FALSE;
}
prev_score = similarity (ivtc, anchor_index - 1, anchor_index);
next_score = similarity (ivtc, anchor_index, anchor_index + 1);
gst_video_frame_map (&dest_frame, &ivtc->src_video_info, outbuf,
GST_MAP_WRITE);
#define THRESHOLD 100
if (prev_score < THRESHOLD) {
if (forward_ok && next_score < prev_score) {
reconstruct (ivtc, &dest_frame, anchor_index, anchor_index + 1);
n_retire = anchor_index + 2;
} else {
if (prev_score >= THRESHOLD / 2) {
GST_INFO ("borderline prev (%d, %d)", prev_score, next_score);
}
reconstruct (ivtc, &dest_frame, anchor_index, anchor_index - 1);
n_retire = anchor_index + 1;
}
} else if (next_score < THRESHOLD) {
if (next_score >= THRESHOLD / 2) {
GST_INFO ("borderline prev (%d, %d)", prev_score, next_score);
}
reconstruct (ivtc, &dest_frame, anchor_index, anchor_index + 1);
if (forward_ok) {
n_retire = anchor_index + 2;
} else {
n_retire = anchor_index + 1;
}
} else {
if (prev_score < THRESHOLD * 2 || next_score < THRESHOLD * 2) {
GST_INFO ("borderline single (%d, %d)", prev_score, next_score);
}
reconstruct_single (ivtc, &dest_frame, anchor_index);
n_retire = anchor_index + 1;
}
GST_DEBUG ("retiring %d", n_retire);
gst_ivtc_retire_fields (ivtc, n_retire);
gst_video_frame_unmap (&dest_frame);
GST_BUFFER_PTS (outbuf) = ivtc->current_ts;
GST_BUFFER_DTS (outbuf) = ivtc->current_ts;
/* FIXME this is not how to produce durations */
GST_BUFFER_DURATION (outbuf) = gst_util_uint64_scale (GST_SECOND,
ivtc->src_video_info.fps_d, ivtc->src_video_info.fps_n);
GST_BUFFER_FLAG_UNSET (outbuf, GST_VIDEO_BUFFER_FLAG_INTERLACED |
GST_VIDEO_BUFFER_FLAG_TFF | GST_VIDEO_BUFFER_FLAG_RFF |
GST_VIDEO_BUFFER_FLAG_ONEFIELD);
ivtc->current_ts += GST_BUFFER_DURATION (outbuf);
}
static int
get_comb_score (GstVideoFrame * top, GstVideoFrame * bottom)
{
int j;
int thisline[MAX_WIDTH];
int score = 0;
int height;
int width;
int k;
height = GST_VIDEO_FRAME_COMP_HEIGHT (top, 0);
width = GST_VIDEO_FRAME_COMP_WIDTH (top, 0);
memset (thisline, 0, sizeof (thisline));
k = 0;
/* remove a few lines from top and bottom, as they sometimes contain
* artifacts */
for (j = 2; j < height - 2; j++) {
guint8 *src1 = GET_LINE_IL (top, bottom, 0, j - 1);
guint8 *src2 = GET_LINE_IL (top, bottom, 0, j);
guint8 *src3 = GET_LINE_IL (top, bottom, 0, j + 1);
int i;
for (i = 0; i < width; i++) {
if (src2[i] < MIN (src1[i], src3[i]) - 5 ||
src2[i] > MAX (src1[i], src3[i]) + 5) {
if (i > 0) {
thisline[i] += thisline[i - 1];
}
thisline[i]++;
if (thisline[i] > 1000)
thisline[i] = 1000;
} else {
thisline[i] = 0;
}
if (thisline[i] > 100) {
score++;
}
}
}
GST_DEBUG ("score %d", score);
return score;
}
static gboolean
plugin_init (GstPlugin * plugin)
{
GST_ELEMENT_REGISTER (ivtc, plugin);
GST_ELEMENT_REGISTER (combdetect, plugin);
return TRUE;
}
GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
GST_VERSION_MINOR,
ivtc,
"Inverse Telecine",
plugin_init, VERSION, "LGPL", PACKAGE_NAME, GST_PACKAGE_ORIGIN)
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