"ACE" Convertor Special Versions

The ACE Converter has four new features (See Zoom Page) which must normally be selected at power-up.
Some special versions have been designed for applications where it is better for these to be ON by default.
There are also other special versions with features normally not available on the standard ACE Converter.
However, please note that for most people the standard unit provides all the facilities they will ever need!


See the Comprehensive Manuals Page for Information Sheets

Special Versions which offer the standard features but with different power-up conditions:

VERSION Default Behaviour of "Digitise" Output Type Held In Momentarily Held In 2.5 Secs Held In 5.0 Secs
(normal) Digitise Video Zoom Letterbox Pillarbox
W Digitise Letterbox Video Zoom Pillarbox
Z Video Zoom Letterbox Pillarbox Digitise
ZW Letterbox Video Zoom Pillarbox Digitise

VERSION Default Behaviour Invert Option Held In Momentarily
(none) Colour Lock OFF Colour Lock ON
L Colour Lock ON Colour Lock OFF

VERSION Default Behaviour Invert Option Held In Momentarily
(none) Auto Input Switching OFF Auto Input Switching ON
S Auto Input Switching ON Auto Input Switching OFF

VERSION Default Behaviour Colour Shift^ Held In Momentarily
(none) Timebase Disable OFF Timebase Disable ON
T Timebase Disable ON Timebase Disable OFF

VERSION Default Behaviour Output Type Button Effect
(none) SCART Output is RGB Switches Output to YUV and back
Y SCART Output is YUV Switches Output to RGB and back

Special Versions which offer extra unusual features which are NOT on the standard unit:

VERSION Special Behaviour
I NEW Inverse Zoom for Image Reduction lets normal monitor act like underscan monitor
B Output Colour Burst Permanently Enabled allows colouring of Monochrome Video
C Colour BLACK Screen Instead Of RED Screen can be useful for preparing new tapes
G GREEN Screen Instead Of RED Screen can be useful for colour background keying
Q Quicker Video and Audio Automatic Fade: 0.5 to 2.5 Secs instead of 1.0 to 5.0 Secs
(H) (Horizontal Zoom Permanently Disabled: original option for Anamorphic Conversion)
M Left/Right Mirror Imaging set by INVERT OPTION with Simplified Video Inversion
N For Noisy TV Signals, e.g. for Amateur TV Reception or ATV Repeater Stations
INVERT OPTION sets Long Time Constant and/or AGC instead of Video Inversion
O Alternative to "N" using "AUDIO" for Time Constant and "MANUAL" for AGC
This keeps normal INVERT OPTION. Fading is Permanently Automatic with Audio
E Freeze Frame (Still Frame) plus Fixed 3200K Colour Temperature Options
Uses "AUDIO" & "MANUAL" controls. Fading is Permanently Automatic with Audio
P Comprehensive Widescreen Signals using the "AUDIO" and "MANUAL" controls
for 4:3/16:9 and FullScreen/Letterbox. Fading is Permanently Automatic with Audio
R Rights Protection & Widescreen Signal using "AUDIO" and "MANUAL" controls
for 4:3/16:9 and CGMS Copy Protection. Fading is Permanently Automatic with Audio
U Horizontal/Vertical Position on Letterbox/Pillarbox using Speed/Manual control
Converted image movement to make room for captions. Uses "MANUAL" as Enable
X Horizontal/Vertical Panning on Letterbox/Pillarbox using Speed/Manual control
Selective cropping of converted images when zoomed. Uses "MANUAL" as Enable
X_VNEW As "X" but with Vertical Panning on Normal Zoom using Speed/Manual control
Selective cropping of expanded images when zoomed. Uses "MANUAL" as Enable

Detailed Explanations of Special Features in Box Above

Inverse Zoom for Image Reduction / Underscan

Underscan Monitors are expensive but it is sometimes useful to be able to see the whole image on a video monitor.

Option "I" replaces the Digitise function with an Inverse Zoom function created by combining Letterboxing with Pillarboxing. In this mode the ACE Converter's normal video zoom function starts from an initial 25% size reduction, i.e. from an underscan position. The standard 5.5% zoom steps then allow the image to be expanded upwards to full size. At a setting of 2 or 3 steps below this the image will be 10% to 15% below normal size so fully visible on all normal (non-underscan) monitors. This new facility thus allows the use of normal monitors as underscan monitors. Existing aspect ratio conversion and zoom facilites are unaffected. The only loss is the Digitise facility, often unused. All other ACE Converter facilities remain unchanged and this new option can be combined with special options Z and/or W and in each case will replace Digitise with Inverse Zoom. In fact we recommend adding Option "Z" to Option "I" unless you wish to use the ACE regularly in Inverse Zoom mode.

Output Colour Burst Permanently Enabled

Normally the Colour Burst on the video output of the ACE will be present only if there is a colour burst present on the video input, as per standard practice. However this can prevent you from adding colour, e.g. sepia, to genuine monochrome video which has no colour burst. Please note though that you can always convert colour video to monochrome and then add colour tints without this special version. There are also some other applications where a permanent colour burst might be useful.

Option "B" ensures the colour burst is always ON. The main disadvantage is that a TV monitor on the output of the ACE will then show colour noise when the ACE is fed with a noisy monochrome video input as the TV's colour decoding circuitry will not be turned off.

BLACK Screen Instead Of RED Screen

The standard ACE Converter offers test patterns which cycle round Normal Video, Colour Bars, Blue Screen and Red Screen. The Blue and Red screens are intended mainly for colour purity checking of picture tubes for which they are the best pair of colours to use.

Option "C" replaces the RED Screen with a Colour Black Screen. This is ideal for recording onto new tapes to give continuous timecode for easier editing. Please note that a Colour Black screen can also be generated on the normal ACE using the fader but only if you provide a continuous colour video source.

GREEN Screen Instead Of RED Screen

The standard ACE Converter offers test patterns which cycle round Normal Video, Colour Bars, Blue Screen and Red Screen. The Blue and Red screens are intended mainly for colour purity checking of picture tubes for which they are the best pair of colours to use.

Option "G" replaces the RED Screen with a GREEN Screen. For colour background keying Blue and Green are the normal colours chosen with Red very rarely used. So this option may be of use to those wishing to use the ACE to generate colours for background keying.

Quicker Video / Audio Automatic Fade

Some people have asked for a faster automatic fade.

Option "Q" reduces the range of the automatic fade times by a factor of 2 from the standard 1.0 to 5.0 Seconds to 0.5 to 2.5 Seconds.

Horizontal Zoom Permanently Disabled

If you wish to convert widescreen video in letterbox format to anamorphic format this requires a vertical expansion. For example to convert from 16:9 letterbox up to full screen height anamorphic format a vertical expansion of 4/3 is required. This can be achieved using the standard "Pillarbox" option which with the zoom in its 6th position is correct for converting 16:9 letterbox to anamorphic.

Alternatively Option "H" permanently disables the horizontal expansion so that vertical-only expansion is possible. The only disadvantage is that the normal combined vertical and horizontal zoom is no longer possible. Now superceded for most applications by Pillarboxing.

Left/Right Mirror Imaging

In videophone applications if the local camera output is fed to the local monitor a lateral inversion is needed for the users to see themselves as if seen through a mirrror which is the normal way we see ourselves. Other applications for lateral inversion include any situation where the camera must view an object or scene through a mirror and this must be corrected.

Normally the INVERT OPTION button cycles around 4 combinations of video and colour inversion. For many people using computer editing this independent control of video and colour inversion, provided mainly for special effects, is no longer required and total video+colour inversion is all that is needed to capture from negatives etc.

Option "M" uses the INVERT OPTION button to cycle through 4 combinations of Video+Colour Inversion and lateral, i.e Left/Right, inversion of the video image. Control Cycling Order is: Normal / Video Invert + Mirror Imaging / Mirror Imaging Only / Video Invert Only.

For Noisy TV Signals

Amateur TV Reception or ATV Repeater Stations often have to cope with very noisy signals. Optimum performance requires a long time constant in the horizontal phase-locked loop so that the ACE can ignore the effects of noise on the sync pulses. On the other hand the standard ACE has a short time constant which was specially chosen for optimum performance with the relatively clean but often jittery video coming off VCRs which must be tracked accurately.

Secondly, since fading TV signals can result in video level changes it is also useful to be able to use the Automatic Gain Control features of the ACE which are normally disabled for optimum performance in normal video applications.

Option "N" uses the INVERT OPTION button to cycle through 4 combinations of Slow and Fast horizontal time constant plus AGC On and Off. The only disadvantage is that the normal video invert options are lost. Control Cycling Order is then: Normal (Fast + AGC Off) / Slow + AGC On / Fast + AGC On / Slow + AGC Off.

Alternative to "N"

If you wish to have the same extra features as option "N" above, prefer not to lose the normal INVERT OPTION features, but don't mind losing some of the fader features and would prefer to have the two new functions on separate latching buttons then please read on!

Option "O" uses the AUDIO button to control the horizontal phase-locked loop (HPLL) time constant and the MANUAL button to control the Automatic Gain Control. The automatic fader is still available with variable speed using the FADE button and SPEED control but fading is always automatic and audio is always faded with the video. Of course audio can be left unfaded simply by connecting audio directly and not taking it via the ACE. Loss of the manual fade is thus the only disadvantage.

AUDIO MANUAL MODE
OUT OUT Fast HPLL + Fixed Gain
OUT IN Fast HPLL + Automatic Gain
IN OUT Slow HPLL + Fixed Gain
IN IN Slow HPLL + Automatic Gain

Freeze Frame + Fixed 3200K Colour Temperature

Option "E" offers a flexible Freeze Frame (Still Frame) facility controlled by the AUDIO button and a Fixed 3200K (incandescent lighting) White Balance / Colour Temperature setting controlled by the MANUAL button. (This option is a spin-off of the ACE24 development.) The automatic fader is still available with variable speed using the FADE button and SPEED control but fading is always automatic and audio is always faded with the video. Of course audio can be left unfaded simply by connecting audio directly and not taking it via the ACE. Loss of the manual fade is thus the only disadvantage.

When in Freeze Frame mode by default both input fields are averaged to remove any motion jitter and then repeated for both output fields. Pressing the INVERT OPTION button allows you to choose from the other three alternatives: Both fields displayed as normal (for best vertical resolution but motion will make the image jitter) or field one or field two repeated (eliminates jitter and avoids the motion blurring caused by averaging but only uses the data from one input field).

Comprehensive Widescreen Signals - Works on 625/50 Output Only

Option "P" has permanent widescreen signalling controlled by AUDIO and MANUAL buttons so widescreen TVs will switch automatically to the correct mode. The automatic fader is still available with variable speed using the FADE button and SPEED control but fading is always automatic and audio is always faded with the video. Of course audio can be left unfaded simply by connecting audio directly and not taking it via the ACE. Loss of the manual fade is thus the only disadvantage.

This option is especially useful with pillarboxing as this will normally be used with a 4:3 source and 16:9 output. Widescreen signalling can then be used to force widescreen TVs into the correct mode. (This option is not usually needed for letterboxing of 16:9 material for 4:3 TVs as they are unlikely to respond to widescreen signalling.) All of the most common modes can be signalled:

AUDIO MANUAL WSS MODE
OUT OUT 4:3 Full Screen
OUT IN 14:9 Letterbox
IN OUT 16:9 Full Screen (Anamorphic)
IN IN 16:9 Letterbox

Rights Protection & Widescreen Signal - Works on 625/50 Output Only

Option "R" has a simplified widescreen signalling controlled by the AUDIO button, so widescreen TVs will switch automatically to the correct mode, and CGMS Copy Protection controlled by the MANUAL button. The automatic fader is still available with variable speed using the FADE button and SPEED control but fading is always automatic and audio is always faded with the video. Of course audio can be left unfaded simply by connecting audio directly and not taking it via the ACE. Loss of the manual fade is thus the only disadvantage.

This option lets you prevent customers from copying VHS tapes of weddings or special interest videos to DVD or DV. It will thus force your customers to make only poorer VHS copies rather than lossless digital ones. The 16:9 widescreen signalling option can be used to force widescreen TVs into the correct mode. All of the most common modes can be signalled:

AUDIO MANUAL WSS & CGMS MODE
OUT OUT 4:3 Full Screen
OUT IN As Above + Copy Protected
IN OUT 16:9 Full Screen (Anamorphic)
IN IN As Above + Copy Protected

Vertical/Horizontal Position on Letterbox/Pillarbox

Option "U" offers Vertical or Horizontal Positioning when using Letterboxing or Pillarboxing with less than maximum Zoom. This allows control over image position to allow the addition of captions or for combining images etc. The MANUAL button is used as an Enable. The AUDIO button works normally. This option can be combined with many other special options but cannot be combined with apparently compatible options M, N, O, E, P or R due to software limitations.

The Speed/Manual control is then used for Positioning, with the Fade being always set to maximum rate (1 second as standard or 0.5 seconds with "Q" Option):

STATE FADE/MANUAL KNOB EFFECT
DIGITISE NONE - NO Positioning
ZOOM NONE - NO Positioning
LETTERBOX Vertical Positioning - Varies with Zoom Level
PILLARBOX Horizontal Positioning - Varies with Zoom Level

Horizontal/Vertical Panning on Letterbox/Pillarbox

Option "X" offers Horizontal or Vertical Panning when using Letterboxing or Pillarboxing with additional Zoom. This allows control over zoom induced cropping for cases where the main focal point of the image is not in the centre. If not combined with Freeze Frame + Fixed 3200K Colour Temperature Option "E" or with Widescreen Signalling / Rights Protection Options "P" and "R" the MANUAL button is used as an Enable, otherwise the panning is permanently active.

The Speed/Manual control is then used for Panning, with the Fade being always set to maximum rate (1 second as standard or 0.5 seconds with "Q" Option):

STATE FADE/MANUAL KNOB EFFECT
DIGITISE NONE - NO Panning
ZOOM NONE - NO Panning
LETTERBOX Horizontal Panning - Varies with Zoom Level
PILLARBOX Vertical Panning - Varies with Zoom Level

Horizontal/Vertical Panning on Letterbox/Pillarbox plus Vertical Panning on Normal Zoom

Option "X_V" gives the same benefits as Option "X" but also offers Vertical Panning when using Normal Zoom. This allows control over zoom induced cropping of expanded images in Letterbox, Pillarbox or Normal Zoom modes for cases where the main focal point of the image is not in the centre. As with Option "X", if Option "X_V" is not combined with Options "E", "P" or "R" the MANUAL button is used as an Enable, otherwise the panning is permanently active.

The Speed/Manual control is then used for Panning, with the Fade being always set to maximum rate (1 second as standard or 0.5 seconds with "Q" Option):

STATE FADE/MANUAL KNOB EFFECT
DIGITISE NONE - NO Panning
ZOOM Vertical Panning - Varies with Zoom Level
LETTERBOX Horizontal Panning - Varies with Zoom Level
PILLARBOX Vertical Panning - Varies with Zoom Level

Copyright GTH Electronics 1997 - 2009

Click Here to Return to the
GTH Home Page

Email to: sales@gthelectronics.com Telephone: 01692 402501 International Tel: +44 1692 402501

Keywords: color, colour, digital, video, processor, standard, convert, converter, red, green, blue, white, balance, contrast, brightness, saturation, hue, sharpness, enhance, invert, aspect, ratio, letterbox, zoom, PAL, NTSC, SECAM, DVD, Betacam, DV, Hi-8, S-VHS, VHS, home cinema, home theater, video processor, colour corrector, corrector, edit, fade, bleed, VCR, bars.