QTeletextMaker

QTeletextMaker is a teletext page editor with an emphasis on Level 2.5 enhancement editing, released under the GNU General Public License v3.0

It is written in C++ using the Qt 6 widget libraries.

Features

• Load and save teletext pages in .tti format.
• Rendering of teletext pages in Levels 1, 1.5, 2.5 and 3.5
• Rendering of Local Objects and side panels.
• Import and export of single pages in .t42 format.
• Export PNG images of teletext pages.
• Undo and redo of editing actions.
• Interactive X/26 Local Enhancement Data triplet editor.
• Editing of X/27/4 and X/27/5 compositional links to enhancement data pages.
• Palette editor.
• Configurable zoom.
• View teletext pages in 4:3, 16:9 pillar-box and 16:9 stretch aspect ratios.

Although designed on and developed for Linux, the Qt libraries are cross platform so a Windows executable can be built. A Windows executable can be found within the "Releases" link, compiled on a Linux host using MXE based on these instructions. After MXE is installed make qtbase should build and install the required dependencies to build QTeletextMaker.

Building

Linux

Install version 6 of the QtCore, QtGui and QtWidgets libraries and build headers, along with CMake.

Change into the source directory and run the following commands. -j8 can be replaced with the number of processor cores used for the compile process

mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
make -j8

The above should place the qteletextmaker executable into the build directory created by the above commands. Within the build directory type ./qteletextmaker in the terminal to launch.

Optionally, type cmake --install . to place the executable into /usr/local/bin and the example .tti files into /usr/local/share/doc/qteletextmaker.

Current limitations

The following X/26 enhancement triplets are not rendered by the editor, although the list is fully aware of them.

• Invocation of Objects from POP and GPOP pages.
• DRCS characters.
• Proportional font spacing on Level 3.5

Using the X/26 triplet editor

The X/26 triplet editor sorts all the triplet modes available into categories, which are:

• Set Active Position
• Row triplet - full screen and full row colours, address row 0 and DRCS mode
• Column triplet - non-spacing attributes and overwriting characters
• Object - invocations and definitions
• Terminator
• PDC/reserved

After selecting the triplet mode the Row and Column spinboxes can then be used to place the Active Position of the selected triplet, whether or not each spinbox can be altered depends on the mode of the selected triplet. As well as the explicit "Set Active Position" triplet that can set both the row and the column, all column triplets can simultaneously set the column of the Active Position. Additionally the Full Row Colour triplet can set the row of the Active Position, with the column always set to 0.

Most triplet modes will present varying widgets below which can be used to alter the parameters of the currently selected triplet e.g. colour or character.

By checking "raw values" it is also possible to view and edit the raw Address, Mode and Data numbers of the triplets. When editing triplets this way, remember that address values 0-39 select a column triplet which has one set of modes and address values 40-63 select a row triplet which has a different set of modes.

The full behaviour of X/26 enhancement triplets can be found in section 12.3 of the Enhanced Teletext specification ETS 300 706.

Setting the Active Position

The Active Position, whether set explicitly by a "Set Active Position" triplet or by a row or column triplet, can only be moved in screen address order i.e. from left to right within a row and then from top to bottom across rows. In other words:

• The Active Position can never be moved up to a lesser numbered row.
• The Active Position can never be moved left within the same row to a lesser numbered column, but it can be moved left at the same time as it is moved down to a greater numbered row.

If this rule is not followed then triplets in earlier screen addresses will be ignored. Triplets that break this rule will be highlighted red in the X/26 triplet editor.

Objects

"Invoke ... Object" triplets must point to a "Define ... Object" of the same type e.g. "Invoke Active Object" must point to a "Define Active Object", otherwise the Object won't appear.