mirror of
https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs.git
synced 2024-05-18 16:28:25 +00:00
767 lines
25 KiB
Rust
767 lines
25 KiB
Rust
// Copyright (C) 2023 Matthew Waters <matthew@centricular.com>
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//
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// This Source Code Form is subject to the terms of the Mozilla Public License, v2.0.
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// If a copy of the MPL was not distributed with this file, You can obtain one at
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// <https://mozilla.org/MPL/2.0/>.
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//
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// SPDX-License-Identifier: MPL-2.0
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use std::collections::VecDeque;
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use cea608_types::{
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tables::{Channel, Color, MidRow, PreambleAddressCode, PreambleType},
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Cea608, Cea608State, Mode,
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};
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use gst::glib;
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use once_cell::sync::Lazy;
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use serde::{Deserialize, Serialize};
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use pango::prelude::*;
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use crate::ccutils::recalculate_pango_layout;
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use gst::prelude::MulDiv;
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static CAT: Lazy<gst::DebugCategory> = Lazy::new(|| {
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gst::DebugCategory::new(
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"cea608utils",
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gst::DebugColorFlags::empty(),
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Some("CEA 608 utilities"),
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)
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});
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#[derive(
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Serialize, Deserialize, Debug, Eq, PartialEq, Ord, PartialOrd, Hash, Clone, Copy, glib::Enum,
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)]
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#[repr(u32)]
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#[enum_type(name = "GstTtToCea608Mode")]
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pub enum Cea608Mode {
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PopOn,
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PaintOn,
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RollUp2,
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RollUp3,
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RollUp4,
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}
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impl From<cea608_types::Mode> for Cea608Mode {
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fn from(value: cea608_types::Mode) -> Self {
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match value {
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cea608_types::Mode::PopOn => Self::PopOn,
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cea608_types::Mode::PaintOn => Self::PaintOn,
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cea608_types::Mode::RollUp2 => Self::RollUp2,
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cea608_types::Mode::RollUp3 => Self::RollUp3,
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cea608_types::Mode::RollUp4 => Self::RollUp4,
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}
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}
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}
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#[derive(Clone, Copy, Serialize, Deserialize, Debug, Default, PartialEq, Eq)]
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pub enum TextStyle {
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#[default]
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White,
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Green,
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Blue,
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Cyan,
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Red,
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Yellow,
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Magenta,
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ItalicWhite,
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}
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impl TextStyle {
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pub fn is_italics(&self) -> bool {
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*self == TextStyle::ItalicWhite
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}
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pub fn to_cea608_color(self) -> Option<cea608_types::tables::Color> {
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match self {
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Self::White => Some(cea608_types::tables::Color::White),
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Self::Green => Some(cea608_types::tables::Color::Green),
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Self::Blue => Some(cea608_types::tables::Color::Blue),
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Self::Cyan => Some(cea608_types::tables::Color::Cyan),
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Self::Red => Some(cea608_types::tables::Color::Red),
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Self::Yellow => Some(cea608_types::tables::Color::Yellow),
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Self::Magenta => Some(cea608_types::tables::Color::Magenta),
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Self::ItalicWhite => None,
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}
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}
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}
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impl From<cea608_types::tables::PreambleAddressCode> for TextStyle {
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fn from(value: cea608_types::tables::PreambleAddressCode) -> Self {
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value.color().into()
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}
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}
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impl From<cea608_types::tables::MidRow> for TextStyle {
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fn from(value: cea608_types::tables::MidRow) -> Self {
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if value.italics() {
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Self::ItalicWhite
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} else {
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// XXX: MidRow may not change color
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value
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.color()
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.unwrap_or(cea608_types::tables::Color::White)
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.into()
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}
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}
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}
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impl From<cea608_types::tables::Color> for TextStyle {
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fn from(value: cea608_types::tables::Color) -> Self {
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match value {
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cea608_types::tables::Color::White => Self::White,
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cea608_types::tables::Color::Green => Self::Green,
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cea608_types::tables::Color::Blue => Self::Blue,
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cea608_types::tables::Color::Cyan => Self::Cyan,
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cea608_types::tables::Color::Red => Self::Red,
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cea608_types::tables::Color::Yellow => Self::Yellow,
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cea608_types::tables::Color::Magenta => Self::Magenta,
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}
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}
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}
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impl From<u32> for TextStyle {
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fn from(val: u32) -> Self {
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match val {
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0 => TextStyle::White,
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1 => TextStyle::Green,
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2 => TextStyle::Blue,
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3 => TextStyle::Cyan,
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4 => TextStyle::Red,
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5 => TextStyle::Yellow,
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6 => TextStyle::Magenta,
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7 => TextStyle::ItalicWhite,
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_ => TextStyle::White,
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}
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}
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}
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const MAX_ROW: usize = 14;
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const MAX_COLUMN: usize = 31;
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#[derive(Debug)]
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pub struct Cea608Frame {
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display_lines: VecDeque<Cea608Line>,
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undisplay_lines: VecDeque<Cea608Line>,
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mode: Option<cea608_types::Mode>,
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selected_channel: Option<cea608_types::tables::Channel>,
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column: usize,
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row: usize,
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base_row: u8,
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preamble: PreambleAddressCode,
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}
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impl Cea608Frame {
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pub fn new() -> Self {
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Self {
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display_lines: VecDeque::new(),
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undisplay_lines: VecDeque::new(),
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mode: None,
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selected_channel: None,
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column: 0,
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row: MAX_ROW,
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base_row: MAX_ROW as u8,
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preamble: PreambleAddressCode::new(0, false, PreambleType::Indent0),
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}
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}
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fn write_lines(&mut self) -> Option<&mut VecDeque<Cea608Line>> {
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match self.mode {
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None => None,
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Some(Mode::PopOn) => Some(&mut self.undisplay_lines),
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_ => Some(&mut self.display_lines),
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}
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}
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fn line_mut(&mut self, row: usize) -> Option<&mut Cea608Line> {
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self.write_lines()
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.and_then(|lines| lines.iter_mut().find(|line| line.no == row))
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}
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fn ensure_cell(&mut self, row: usize, column: usize) {
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let line = if let Some(line) = self.line_mut(row) {
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line
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} else {
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let Some(lines) = self.write_lines() else {
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return;
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};
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lines.push_back(Cea608Line {
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no: row,
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line: VecDeque::new(),
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initial_preamble: None,
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});
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lines.back_mut().unwrap()
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};
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while line.line.len() <= column {
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line.line.push_back(Cea608Cell::Empty);
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}
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}
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fn cell_mut(&mut self, row: usize, column: usize) -> Option<&mut Cea608Cell> {
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self.write_lines().and_then(|lines| {
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lines
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.iter_mut()
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.find(|line| line.no == row)
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.and_then(|line| line.line.get_mut(column))
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})
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}
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fn reset(&mut self) {
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self.display_lines.clear();
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self.undisplay_lines.clear();
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self.mode = None;
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self.column = 0;
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self.selected_channel = None;
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}
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pub fn set_channel(&mut self, channel: Channel) {
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if Some(channel) != self.selected_channel {
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self.reset();
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self.selected_channel = Some(channel);
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}
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}
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pub fn push_code(&mut self, cea608: Cea608) -> bool {
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if self.selected_channel.is_none() {
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self.selected_channel = Some(cea608.channel());
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}
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if Some(cea608.channel()) != self.selected_channel {
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return false;
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}
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match cea608 {
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Cea608::Text(text) => {
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let mut ret = false;
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if text.needs_backspace {
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ret |= self.backspace();
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}
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if let Some(c) = text.char1 {
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ret |= self.push_char(c);
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}
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if let Some(c) = text.char2 {
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ret |= self.push_char(c);
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}
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ret
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}
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Cea608::NewMode(_chan, new_mode) => self.new_mode(new_mode),
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Cea608::Preamble(_chan, preamble) => self.preamble(preamble),
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Cea608::EraseDisplay(_chan) => {
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self.display_lines.clear();
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true
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}
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Cea608::EraseNonDisplay(_chan) => {
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self.undisplay_lines.clear();
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false
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}
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Cea608::EndOfCaption(_chan) => {
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std::mem::swap(&mut self.display_lines, &mut self.undisplay_lines);
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self.new_mode(cea608_types::Mode::PopOn);
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true
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}
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Cea608::Backspace(_chan) => self.backspace(),
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Cea608::TabOffset(_chan, n_tabs) => {
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self.column = (self.column + n_tabs as usize).min(MAX_COLUMN);
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false
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}
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Cea608::MidRowChange(_chan, midrow) => self.midrow(midrow),
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Cea608::CarriageReturn(_chan) => self.carriage_return(),
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Cea608::DeleteToEndOfRow(_chan) => self.delete_to_end_of_row(),
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}
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}
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fn push_char(&mut self, c: char) -> bool {
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let row = self.mode.map_or(self.row, |mode| {
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if mode.is_rollup() {
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self.base_row as usize
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} else {
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self.row
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}
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});
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self.ensure_cell(row, self.column);
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if self.column == 0 {
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let preamble = self.preamble;
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let Some(line) = self.line_mut(row) else {
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return false;
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};
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line.initial_preamble = Some(preamble);
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}
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let Some(cell) = self.cell_mut(row, self.column) else {
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return false;
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};
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*cell = Cea608Cell::Char(c);
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self.column = (self.column + 1).min(MAX_COLUMN);
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true
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}
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fn new_mode(&mut self, new_mode: cea608_types::Mode) -> bool {
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if Some(new_mode) == self.mode {
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return false;
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}
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// if we are changing to roll up mode, we need to reset
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if new_mode.is_rollup()
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&& !self
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.mode
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.map_or(!new_mode.is_rollup(), |mode| mode.is_rollup())
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{
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self.base_row = MAX_ROW as u8;
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self.reset();
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}
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self.mode = Some(new_mode);
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if new_mode.is_rollup() {
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self.column = 0;
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// XXX: do we need to move any existing captions?
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}
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true
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}
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fn preamble(&mut self, preamble: PreambleAddressCode) -> bool {
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self.preamble = preamble;
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self.column = preamble.column() as usize;
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let Some(mode) = self.mode else {
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self.row = preamble.row() as usize;
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return false;
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};
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match mode {
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Mode::PopOn | Mode::PaintOn => {
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self.row = preamble.row() as usize;
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}
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Mode::RollUp2 | Mode::RollUp3 | Mode::RollUp4 => {
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let base_row = preamble.row().max(mode.rollup_rows().unwrap_or(0));
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if self.base_row != base_row {
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gst::debug!(
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CAT,
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"roll up base row change from {} to {base_row}",
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self.base_row
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);
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let diff = base_row as i8 - self.base_row as i8;
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self.display_lines.retain(|line| {
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(0..=MAX_ROW as isize).contains(&(line.no as isize + diff as isize))
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});
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for line in self.display_lines.iter_mut() {
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line.no = (line.no as isize + diff as isize) as usize;
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}
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self.base_row = preamble.row();
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}
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}
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}
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true
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}
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fn midrow(&mut self, midrow: MidRow) -> bool {
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self.ensure_cell(self.row, self.column);
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let Some(cell) = self.cell_mut(self.row, self.column) else {
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return false;
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};
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*cell = Cea608Cell::MidRow(midrow);
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self.column = (self.column + 1).min(MAX_COLUMN);
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true
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}
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fn carriage_return(&mut self) -> bool {
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if !matches!(
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self.mode,
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Some(
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cea608_types::Mode::RollUp2
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| cea608_types::Mode::RollUp3
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| cea608_types::Mode::RollUp4
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)
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) {
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// no-op for non roll up modes
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return false;
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}
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let n_rows = self.mode.unwrap().rollup_rows().unwrap();
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self.display_lines
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.retain(|line| line.no > (self.base_row - n_rows + 1) as usize);
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for line in self.display_lines.iter_mut() {
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line.no -= 1;
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}
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self.column = 0;
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true
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}
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fn backspace(&mut self) -> bool {
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if self.column == 0 {
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return false;
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}
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self.ensure_cell(self.row, self.column - 1);
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let Some(cell) = self.cell_mut(self.row, self.column - 1) else {
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return false;
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};
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*cell = Cea608Cell::Empty;
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self.column -= 1;
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true
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}
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fn delete_to_end_of_row(&mut self) -> bool {
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let column = self.column;
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let Some(line) = self.line_mut(self.row) else {
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return false;
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};
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while line.line.len() > column {
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line.line.pop_back();
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}
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true
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}
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pub fn iter(&self) -> impl Iterator<Item = &Cea608Line> {
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self.display_lines.iter()
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}
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pub fn get_text(&self) -> String {
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let mut text = String::new();
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for (i, line) in self.iter().enumerate() {
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let mut seen_non_space = false;
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if i != 0 {
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text.push('\r');
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text.push('\n');
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}
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for (_i, c) in line.display_iter() {
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match c {
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Cea608Cell::Empty | Cea608Cell::MidRow(_) => {
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if seen_non_space {
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text.push(' ')
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}
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}
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Cea608Cell::Char(c) => {
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if *c != ' ' {
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seen_non_space = true;
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}
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text.push(*c);
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}
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}
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}
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}
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text
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}
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pub fn mode(&self) -> Option<cea608_types::Mode> {
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self.mode
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}
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}
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#[derive(Debug)]
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pub struct Cea608Line {
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no: usize,
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line: VecDeque<Cea608Cell>,
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initial_preamble: Option<PreambleAddressCode>,
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}
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impl Cea608Line {
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pub fn initial_preamble(&self) -> PreambleAddressCode {
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self.initial_preamble
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.unwrap_or_else(|| PreambleAddressCode::new(0, false, PreambleType::Indent0))
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}
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pub fn display_iter(&self) -> impl Iterator<Item = (usize, &Cea608Cell)> {
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self.line.iter().enumerate()
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}
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}
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#[derive(Debug)]
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pub enum Cea608Cell {
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Empty,
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Char(char),
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MidRow(cea608_types::tables::MidRow),
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}
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fn pango_foreground_color_from_608(color: Color) -> pango::AttrColor {
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let (r, g, b) = match color {
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Color::White => (u16::MAX, u16::MAX, u16::MAX),
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Color::Green => (0, u16::MAX, 0),
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Color::Blue => (0, 0, u16::MAX),
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Color::Cyan => (0, u16::MAX, u16::MAX),
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Color::Red => (u16::MAX, 0, 0),
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Color::Yellow => (u16::MAX, u16::MAX, 0),
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Color::Magenta => (u16::MAX, 0, u16::MAX),
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};
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pango::AttrColor::new_foreground(r, g, b)
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}
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pub struct Cea608Renderer {
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frame: Cea608Frame,
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state: Cea608State,
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context: pango::Context,
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layout: pango::Layout,
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rectangle: Option<gst_video::VideoOverlayRectangle>,
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video_width: u32,
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video_height: u32,
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left_alignment: i32,
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black_background: bool,
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}
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impl Cea608Renderer {
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pub fn new() -> Self {
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let video_width = 0;
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let video_height = 0;
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let fontmap = pangocairo::FontMap::new();
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let context = fontmap.create_context();
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context.set_language(Some(&pango::Language::from_string("en_US")));
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context.set_base_dir(pango::Direction::Ltr);
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let layout = pango::Layout::new(&context);
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layout.set_alignment(pango::Alignment::Left);
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let left_alignment = recalculate_pango_layout(&layout, video_width, video_height);
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Self {
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frame: Cea608Frame::new(),
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state: Cea608State::default(),
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context,
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layout,
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rectangle: None,
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video_width,
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video_height,
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left_alignment,
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black_background: false,
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}
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}
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pub fn push_pair(&mut self, pair: [u8; 2]) -> Result<bool, cea608_types::ParserError> {
|
|
if let Some(cea608) = self.state.decode(pair)? {
|
|
gst::trace!(CAT, "Decoded {cea608:?}");
|
|
if self.frame.push_code(cea608) {
|
|
self.rectangle.take();
|
|
return Ok(true);
|
|
}
|
|
}
|
|
Ok(false)
|
|
}
|
|
|
|
pub fn set_channel(&mut self, channel: cea608_types::tables::Channel) {
|
|
if self.frame.selected_channel != Some(channel) {
|
|
self.frame.set_channel(channel);
|
|
self.rectangle.take();
|
|
}
|
|
}
|
|
|
|
pub fn set_video_size(&mut self, width: u32, height: u32) {
|
|
if width != self.video_width || height != self.video_height {
|
|
self.video_width = width;
|
|
self.video_height = height;
|
|
self.layout = pango::Layout::new(&self.context);
|
|
self.layout.set_alignment(pango::Alignment::Left);
|
|
self.left_alignment = recalculate_pango_layout(&self.layout, width, height);
|
|
self.rectangle.take();
|
|
}
|
|
}
|
|
|
|
pub fn set_black_background(&mut self, bg: bool) {
|
|
self.black_background = bg;
|
|
self.rectangle.take();
|
|
}
|
|
|
|
pub fn generate_rectangle(&mut self) -> Option<gst_video::VideoOverlayRectangle> {
|
|
if let Some(rectangle) = self.rectangle.clone() {
|
|
return Some(rectangle);
|
|
}
|
|
|
|
// 1. generate pango layout
|
|
let mut text = String::new();
|
|
let attrs = pango::AttrList::new();
|
|
if self.black_background {
|
|
let attr = pango::AttrColor::new_background(0, 0, 0);
|
|
attrs.insert(attr);
|
|
}
|
|
|
|
let mut first_row = 0;
|
|
let mut last_row = None;
|
|
for line in self.frame.iter() {
|
|
if let Some(last_row) = last_row {
|
|
for _ in 0..line.no - last_row {
|
|
text.push('\n');
|
|
}
|
|
} else {
|
|
first_row = line.no;
|
|
}
|
|
last_row = Some(line.no);
|
|
|
|
let idx = text.len() as u32;
|
|
let initial = line.initial_preamble();
|
|
|
|
let mut foreground_color_attr = pango_foreground_color_from_608(initial.color());
|
|
foreground_color_attr.set_start_index(idx);
|
|
let mut last_color = initial.color();
|
|
|
|
let mut underline_attr = pango::AttrInt::new_underline(if initial.underline() {
|
|
pango::Underline::Single
|
|
} else {
|
|
pango::Underline::None
|
|
});
|
|
underline_attr.set_start_index(idx);
|
|
let mut last_underline = initial.underline();
|
|
|
|
let mut italic_attr = if initial.italics() {
|
|
let mut attr = pango::AttrInt::new_style(pango::Style::Italic);
|
|
attr.set_start_index(idx);
|
|
Some(attr)
|
|
} else {
|
|
None
|
|
};
|
|
|
|
for (_char_no, cell) in line.display_iter() {
|
|
match cell {
|
|
Cea608Cell::MidRow(midrow) => {
|
|
text.push(' ');
|
|
let idx = text.len() as u32;
|
|
|
|
if last_underline != midrow.underline() {
|
|
underline_attr.set_end_index(idx);
|
|
attrs.insert(underline_attr);
|
|
underline_attr = pango::AttrInt::new_underline(if midrow.underline() {
|
|
pango::Underline::Single
|
|
} else {
|
|
pango::Underline::None
|
|
});
|
|
underline_attr.set_start_index(idx);
|
|
last_underline = midrow.underline();
|
|
}
|
|
|
|
if !midrow.italics() {
|
|
if let Some(mut italic) = italic_attr.take() {
|
|
italic.set_end_index(idx);
|
|
attrs.insert(italic);
|
|
}
|
|
} else if midrow.italics() && italic_attr.is_none() {
|
|
let mut attr = pango::AttrInt::new_style(pango::Style::Italic);
|
|
attr.set_start_index(idx);
|
|
italic_attr = Some(attr);
|
|
}
|
|
|
|
if let Some(color) = midrow.color() {
|
|
if color != last_color {
|
|
foreground_color_attr.set_end_index(idx);
|
|
attrs.insert(foreground_color_attr);
|
|
foreground_color_attr = pango_foreground_color_from_608(color);
|
|
foreground_color_attr.set_start_index(idx);
|
|
last_color = color;
|
|
}
|
|
}
|
|
}
|
|
Cea608Cell::Empty => text.push(' '),
|
|
Cea608Cell::Char(c) => text.push(*c),
|
|
}
|
|
}
|
|
|
|
let idx = text.len() as u32;
|
|
|
|
foreground_color_attr.set_end_index(idx);
|
|
attrs.insert(foreground_color_attr);
|
|
underline_attr.set_end_index(idx);
|
|
attrs.insert(underline_attr);
|
|
if let Some(mut italics) = italic_attr.take() {
|
|
italics.set_end_index(idx);
|
|
attrs.insert(italics);
|
|
}
|
|
}
|
|
|
|
// 2. render text
|
|
self.layout.set_text(&text);
|
|
self.layout.set_attributes(Some(&attrs));
|
|
let (_ink_rect, logical_rect) = self.layout.extents();
|
|
let height = logical_rect.height() / pango::SCALE;
|
|
let width = logical_rect.width() / pango::SCALE;
|
|
gst::debug!(CAT, "overlaying size {width}x{height}, text {text}");
|
|
|
|
// No text actually needs rendering
|
|
if width == 0 || height == 0 {
|
|
return None;
|
|
}
|
|
|
|
let render_buffer = || -> Option<gst::Buffer> {
|
|
let mut buffer = gst::Buffer::with_size((width * height) as usize * 4).ok()?;
|
|
|
|
gst_video::VideoMeta::add(
|
|
buffer.get_mut().unwrap(),
|
|
gst_video::VideoFrameFlags::empty(),
|
|
#[cfg(target_endian = "little")]
|
|
gst_video::VideoFormat::Bgra,
|
|
#[cfg(target_endian = "big")]
|
|
gst_video::VideoFormat::Argb,
|
|
width as u32,
|
|
height as u32,
|
|
)
|
|
.ok()?;
|
|
let buffer = buffer.into_mapped_buffer_writable().unwrap();
|
|
|
|
// Pass ownership of the buffer to the cairo surface but keep around
|
|
// a raw pointer so we can later retrieve it again when the surface
|
|
// is done
|
|
let buffer_ptr = buffer.buffer().as_ptr();
|
|
let surface = cairo::ImageSurface::create_for_data(
|
|
buffer,
|
|
cairo::Format::ARgb32,
|
|
width,
|
|
height,
|
|
width * 4,
|
|
)
|
|
.ok()?;
|
|
|
|
let cr = cairo::Context::new(&surface).ok()?;
|
|
|
|
// Clear background
|
|
cr.set_operator(cairo::Operator::Source);
|
|
cr.set_source_rgba(0.0, 0.0, 0.0, 0.0);
|
|
cr.paint().ok()?;
|
|
|
|
// Render text outline
|
|
cr.save().ok()?;
|
|
cr.set_operator(cairo::Operator::Over);
|
|
|
|
cr.set_source_rgba(0.0, 0.0, 0.0, 1.0);
|
|
|
|
pangocairo::functions::layout_path(&cr, &self.layout);
|
|
cr.stroke().ok()?;
|
|
cr.restore().ok()?;
|
|
|
|
// Render text
|
|
cr.save().ok()?;
|
|
cr.set_source_rgba(255.0, 255.0, 255.0, 1.0);
|
|
|
|
pangocairo::functions::show_layout(&cr, &self.layout);
|
|
|
|
cr.restore().ok()?;
|
|
drop(cr);
|
|
|
|
// Safety: The surface still owns a mutable reference to the buffer but our reference
|
|
// to the surface here is the last one. After dropping the surface the buffer would be
|
|
// freed, so we keep an additional strong reference here before dropping the surface,
|
|
// which is then returned. As such it's guaranteed that nothing is using the buffer
|
|
// anymore mutably.
|
|
unsafe {
|
|
assert_eq!(
|
|
cairo::ffi::cairo_surface_get_reference_count(surface.to_raw_none()),
|
|
1
|
|
);
|
|
let buffer = glib::translate::from_glib_none(buffer_ptr);
|
|
drop(surface);
|
|
buffer
|
|
}
|
|
};
|
|
|
|
let buffer = match render_buffer() {
|
|
Some(buffer) => buffer,
|
|
None => {
|
|
gst::error!(CAT, "Failed to render buffer");
|
|
return None;
|
|
}
|
|
};
|
|
|
|
let vertical_padding = self.video_height / 10;
|
|
let safe_height = self.video_height.mul_div_floor(80, 100).unwrap();
|
|
let first_row_position = (safe_height as i32)
|
|
.mul_div_round(first_row as i32, MAX_ROW as i32 + 1)
|
|
.unwrap();
|
|
|
|
let rect = gst_video::VideoOverlayRectangle::new_raw(
|
|
&buffer,
|
|
self.left_alignment,
|
|
first_row_position + vertical_padding as i32,
|
|
width as u32,
|
|
height as u32,
|
|
gst_video::VideoOverlayFormatFlags::PREMULTIPLIED_ALPHA,
|
|
);
|
|
|
|
self.rectangle = Some(rect.clone());
|
|
Some(rect)
|
|
}
|
|
}
|