Convert set of PNG files to MPG, MP4 or AVI file

[NY]

A bit of a long shot...

I have a Super 8 home movie which was converted to an AVI file. However
every third frame is a merger of fields from two adjacent frames, so if the
frames in the original film were numbered 1 2 3 4 5 etc then the video has
1, 2, 3+4, 4, 5, 6+7, 7, 8, 9+10, etc.

I want to remove the combined frames from the AVI file.

I've found some software (Prism, by NCH) which can take an AVI file as input
and output a sequence of consecutively numbered PNG files. Removing the bad
ones is a case of writing a program which deletes every third file.

But... is there any software which will take the sequence of remaining PNG
files and reassemble them into a video file in a format such as MPEG-2, MP4
(H264) or AVI, adding a silent audio stream so the file is valid (many
packages can't read in an MPG file which has no audio stream).


(Background: the film is a journey in the car as my dad drove around town
with me clicking the shutter every second, so it's horrendously speeded up.
I want to slow it down a bit by duplicating every frame n times which Adobe
Premiere Elements can do, but that makes the half-and-half frames very
intrusive, and they don't add anything and actually make the movement more
jerky because every third film frame is shown twice. At least the
frame-duplicated film will be consistently jerky without the present
move,move.pause,move,move,pause motion!)

[Andy Burns]

Post by NY
I have a Super 8 home movie which was converted to an AVI file. However
every third frame is a merger of fields from two adjacent frames, so if the
frames in the original film were numbered 1 2 3 4 5 etc then the video has
1, 2, 3+4, 4, 5, 6+7, 7, 8, 9+10, etc.
I want to remove the combined frames from the AVI file.

Any chance an inverse-telecine effect will do what you want?

[Wolfgang Schwanke]

Post by NY
But... is there any software which will take the sequence of remaining
PNG files and reassemble them into a video file in a format such as
MPEG-2, MP4 (H264) or AVI, adding a silent audio stream so the file is
valid (many packages can't read in an MPG file which has no audio
stream).

AviSynth, VirtualDub, VidEdit

Avisynth is really a scripting language, but very powerful.

VidEdit is a small Video Editor shipped with the original "Video for
Windows" Suite from Microsoft. It's an ancient 16 Bit application but
if you happen to have it lying around .. I think it reads BMP only, so
you have to batch convert the PNG files first.

Post by NY
I have a Super 8 home movie which was converted to an AVI file.
However every third frame is a merger of fields from two adjacent
frames, so if the frames in the original film were numbered 1 2 3 4 5
etc then the video has 1, 2, 3+4, 4, 5, 6+7, 7, 8, 9+10, etc.

How did that happen? Super8 are normally 18fps, so if some of the
frames are merged it was digitised at a frame rate even lower than
that. That i s not really good. If you can digitise it again you
should, preferrably at 18fps or 25fps. 18 would be logically ideal, but
it's non-standard. If you want to say make a DVD or play it through
some other device to a television, 25 ought to be the target frame rate.

Post by NY
I want to remove the combined frames from the AVI file.

You will get jumpy motion though. Short of redigitising it, it might be
better to leave it as it is.

[NY]

Post by Wolfgang Schwanke

Post by NY
I have a Super 8 home movie which was converted to an AVI file.
However every third frame is a merger of fields from two adjacent
frames, so if the frames in the original film were numbered 1 2 3 4 5
etc then the video has 1, 2, 3+4, 4, 5, 6+7, 7, 8, 9+10, etc.

How did that happen? Super8 are normally 18fps, so if some of the
frames are merged it was digitised at a frame rate even lower than
that. That i s not really good. If you can digitise it again you
should, preferrably at 18fps or 25fps. 18 would be logically ideal, but
it's non-standard. If you want to say make a DVD or play it through
some other device to a television, 25 ought to be the target frame rate.

I wonder if the firm that telecined it played the film at 18 fps but ran the
capture device at 25 fps. Certainly the AVI files are 25 fps. This would
have the effect of showing some frames once and some twice (as a field from
one frame and a field from the next). For normal cine, shot at 18 (or even
24) fps, that's not a problem: when played at normal speed you don't notice
the blur too much. But for this particular film, which was shot as stop
motion at roughly 1 fps, it becomes noticeable if you decide to slow it down
by doubling or trebling each frame.

Post by Wolfgang Schwanke

Post by NY
I want to remove the combined frames from the AVI file.

You will get jumpy motion though. Short of redigitising it, it might be
better to leave it as it is.

Yes it's not brilliant but I've managed to improve on what I had originally.

For anyone that's interested, the workflow is as follows:

1. Use Prism to save the original AVI file as lots of PNG files, one per
frame. A standard 50 foot Super 8 film consists of about 5500 frames.

2. Open the folder containing these files in Windows Explorer; display the
files as icons and reduce the width of the window so the thumbnails are
displayed in 3 columns (I want to delete every third frame)

3. Identify the "bad" column which consists entirely of merged frames.

4. Put the cursor to the top left of the first frame in that column, press
and hold left mouse and move the mouse the bottom of the window, in the same
horizontal position. The list of files scrolls rapidly down, selecting just
the pictures in the "bad" column.

5. Press Delete.

6. Having now got rid of the bad frames, I open Premiere Elements (I've got
V11).

7. Create a new project: PAL, DV, non-widescreen.

8. Press Add Media

9. Go to the Windows Explorer window which contains the files. Ctrl-A to
select all, then drag and drop them onto the Add Media window in Premiere -
this takes a minute or so to complete.

10. Save the project!

11. Select a group of frames (initially I tried selecting all 5500 but this
crashed Premiere, so I repeated with chunks of about 1000.

12. Right-click, Create Slideshow

13. Image duration 2 frames, untick "Apply Default Transformation", OK (I
chose 2 to show each frame twice: adjust this value to taste!)

14. This adds the chosen frames as a sequence into the timeline of the
movie. Save the project!

15. I repeated steps 11-14 until I'd added all the frames.

16. Finally, Publish and Share, For Computer, MPEG, PAL DVD standard. Wait
while everything renders - took about 5 mins on my computer.

[Wolfgang Schwanke]

Post by NY
I wonder if the firm that telecined it played the film at 18 fps but
ran the capture device at 25 fps.

If they'd done that you would get something like:

1 2 3 3+4 4 5 6 7 7+8 8 9 ..

So while you would also get blurred frames, you would have a clear
version of each original frame. But you described the sequence as some
frames existing only in a version blurred with its successor, so I
think that's not what they did.

I have another idea. You said you have

1 2 3+4 4 5 6+7 7

You could synthesize the missing frames by substracting the
corresponding successor, i.e.:

Take the blended 3+4 and substract all the pixel values of 4. You
should get a clear version of 3 back. That is better than throwing away
all the blurred frames. This would have to be done with an image
scripting tool, such as ImageMagick.

Post by NY
But for this
particular film, which was shot as stop motion at roughly 1 fps, it
becomes noticeable if you decide to slow it down by doubling or
trebling each frame.

You did stop motion in Super 8? :)

[NY]

Post by Wolfgang Schwanke

Post by NY
I wonder if the firm that telecined it played the film at 18 fps but
ran the capture device at 25 fps.

1 2 3 3+4 4 5 6 7 7+8 8 9 ..

I'm an idiot. I got the numbering wrong. It was 1 2 2+3 3 4 4+5 5 6 etc. So
I just removed every third frame to get 1 2 3 4 5 6. And then trebled each
frame to give 1 1 1 2 2 2 3 3 3 4 4 4 to slow down the motion a bit at the
expense of making it more jerky. At least it was constant-motion jerkiness
rather than irregular motion where every third frame was a repeat of the one
before (with the one yet to come blended in with it). Sadly the telecine
house ignored my instructions "can you run this one at 25 fps rather than 18
fps so every film frame corresponds with exactly one video frame".

Post by Wolfgang Schwanke

Post by NY
But for this
particular film, which was shot as stop motion at roughly 1 fps, it
becomes noticeable if you decide to slow it down by doubling or
trebling each frame.

You did stop motion in Super 8? :)

Yes: I remember my dad set up two long baulks of wood side by side, which
rested on the dashboard and on the back of the front passenger seat, with
the camera lashed to them somehow. I sat in the seat, in between the wood,
and somehow even managed to get my seat belt on. All hideously unsafe, I'm
sure. As dad drove around town and past my school, I was there with the
cable release from the camera, clicking away at roughly once a second. I
remember dad had to put an elastic band round the normal shutter release to
half-press it to turn on the exposure meter without setting the film running
at normal 18 or 25 fps. At one point during the journey there was a ping and
the band slipped off, so several seconds of the film are very over-exposed
until he stopped and sorted it out! From the fact that we drove along a road
that was pedestrianised a year or so later, we can date the film to 1973 or
1974. Interesting to see what's changed and what's still very recognisable.
I've put it on Youtube:

Maybe some time when we get our car dashcam, I'll drive as much of the route
as I can to do a comparison film, if I find myself over that way.

Somewhere in among the films that we got digitised a few years ago is one
that dad made, either with that Super 8 camera or else with an older
Standard 8 camera, using stop motion where he animated some of my Dinky toys
driving along a toy road. Nowadays it would be easy with a video camera or
even a still camera to take a series of still photos and animate them
together into a video - and without needing a bright Photoflood light
indoors, too!

[Wolfgang Schwanke]

Post by NY
I'm an idiot. I got the numbering wrong. It was 1 2 2+3 3 4 4+5 5 6
etc. So I just removed every third frame to get 1 2 3 4 5 6.

OK, so you're good.

Post by NY
http://youtu.be/f3eZB2QNvtM

+1

Maybe you could do a second version without tripling the frames. Tastes
differ, but I think I'd prefer it that way because it would give a
smoother motion. And you could probably correct the overexposed bit in
Premiere Elements.

Post by NY
Maybe some time when we get our car dashcam, I'll drive as much of the
route as I can to do a comparison film, if I find myself over that
way.

And perhaps edit them into one synchronised, side by side or one in a
small window inside the other?

[NY]

Post by Wolfgang Schwanke

Post by NY
I'm an idiot. I got the numbering wrong. It was 1 2 2+3 3 4 4+5 5 6
etc. So I just removed every third frame to get 1 2 3 4 5 6.

OK, so you're good.

Post by NY
http://youtu.be/f3eZB2QNvtM

+1
Maybe you could do a second version without tripling the frames. Tastes
differ, but I think I'd prefer it that way because it would give a
smoother motion.

I've just done a version without tripling the frames. Here it is:

Post by Wolfgang Schwanke
And you could probably correct the overexposed bit in
Premiere Elements.

I'll see how I get on with correcting the exposed bit. I was forgetting that
I could do that in Premiere. If I manage to do it for a still frame, and it
looks to be a significant improvement, I'll apply the same sort of
correction to the video.

Post by Wolfgang Schwanke

Post by NY
Maybe some time when we get our car dashcam, I'll drive as much of the
route as I can to do a comparison film, if I find myself over that
way.

And perhaps edit them into one synchronised, side by side or one in a
small window inside the other?

Now that would be a good idea. There would be parts in the centre of town
where I probably couldn't go by car, but I wonder if I could take my bike
and cycle those bits - maybe even (walking and pushing my bike) on the
pedestrianised bit. It's a shame that roads have been rerouted here and
there. Keeping everything in sync will be "fun" :-) I might need to time the
route between key points in the original film and apply a similar speed-up
factor for the present-day video. Seeing how places have changed is always
intriguing. I wonder if any of the cars in the film are still on the road.
The only three whose number I can read (the red/orange Escort just after
going under the railway bridge, the Cortina Mk 2 as we turn left towards the
Cathedral and the white Beetle at the traffic lights shortly afterwards),
don't appear on the DVLA site. Mum's Morris Minor UBL 242 on our drive at
home went to the scrapyard many years ago, after seeing out her final days
as the first car of my dad's secretary's daughter.

[Wolfgang Schwanke]

Post by NY
http://youtu.be/7oA6ZJXmgck

I like this better because the motion is fluid.

[split screen]

Post by NY
I might need to time the route between key points in the original film
and apply a similar speed-up factor for the present-day video.

Yes, that is probably the best approach. Timing every sequence to the
exact length while filming would be a logistical nightmare.

I've done a completely different split screen video, a landing of a
small plane on a provincial airport. The front camera is fixed, the
other two are handheld out of the right window. Of course everything is
filmed in realtime and synced by definition. Two of the cameras are
30fps digital ones, one is a PAL analogue camcorder. I converted
everything to 576/25 and edited from there in Premiere.

[NY]

Post by Wolfgang Schwanke

Post by NY
Maybe some time when we get our car dashcam, I'll drive as much of the
route as I can to do a comparison film, if I find myself over that
way.

And perhaps edit them into one synchronised, side by side or one in a
small window inside the other?

Until I get round to filming the modern route properly with a camcorder,
here is a crude version made up of Google Streetview images

This is the same route as the 1973 footage, apart from a few locations where
junctions or roads have been realigned, and a section in the city centre
where some roads have been closed to cars (including the Google car) or have
been pedestrianised.

This is fairly crude footage generated by following the route in GMap
Pedometer http://www.gmap-pedometer.com/ to make a GPX file, and then using
Google Maps Streetview Player http://brianfolts.com/driver/ to produce an
animated GIF of the Streetview images from which I've made an MPEG.
Unfortunately those images are titled upwards so there's a lot of sky.

[Dave W]

"NY" <***@privacy.net> wrote in message news:RMednRP-***@brightview.co.uk...
<snip>

Post by NY
This is fairly crude footage generated by following the route in GMap
Pedometer http://www.gmap-pedometer.com/ to make a GPX file, and then
using Google Maps Streetview Player http://brianfolts.com/driver/ to
produce an animated GIF of the Streetview images from which I've made an
MPEG. Unfortunately those images are titled upwards so there's a lot of
sky.

Thanks for introducing us to these two interesting sites. I tried out the
pedometer one, going for a virtual walk (or "run" as it calls it) to the
shops in Epsom and back by a different route. Unfortunately the footpaths
did not register, and I was forced to go via the roads. Also there were
little kinks in the track at side roads, because I used the "automatic"
route-following method rather than manually drawing straight lines.

Then putting the gpx file into Brian Folts's website, the resultant animated
gif made Streetview turn round at the kinks, spoiling the journey by looking
at houses. Only a centre section of the 360 degree Streetview image is used
for the gif, and turns are created by using the same image twice but rotated
a bit. The images are not tilted up but show a horizontal view, but far more
sky is shown than the ground.

My file contained about 90 frames shown at 1 second intervals, and was about
14MB. I thought about shifting some of the images sideways to make the
journey smoother, but it wasn't practicable, and I just removed some
offending frames using Adobe ImageReady (included with an old free Photoshop
download).

It might be better to select and position each image directly from
Streetview, with minimum travel between each one, but of course that would
take very much time and effort.
--
Dave W

[Dave W]

Post by NY

Post by Wolfgang Schwanke

Post by NY
I wonder if the firm that telecined it played the film at 18 fps but
ran the capture device at 25 fps.

1 2 3 3+4 4 5 6 7 7+8 8 9 ..

I'm an idiot. I got the numbering wrong. It was 1 2 2+3 3 4 4+5 5 6 etc.
So I just removed every third frame to get 1 2 3 4 5 6. And then trebled
each frame to give 1 1 1 2 2 2 3 3 3 4 4 4 to slow down the motion a bit
at the expense of making it more jerky. At least it was constant-motion
jerkiness rather than irregular motion where every third frame was a
repeat of the one before (with the one yet to come blended in with it).
Sadly the telecine house ignored my instructions "can you run this one at
25 fps rather than 18 fps so every film frame corresponds with exactly one
video frame".

Post by Wolfgang Schwanke

Post by NY
But for this
particular film, which was shot as stop motion at roughly 1 fps, it
becomes noticeable if you decide to slow it down by doubling or
trebling each frame.

You did stop motion in Super 8? :)

Yes: I remember my dad set up two long baulks of wood side by side, which
rested on the dashboard and on the back of the front passenger seat, with
the camera lashed to them somehow. I sat in the seat, in between the wood,
and somehow even managed to get my seat belt on. All hideously unsafe, I'm
sure. As dad drove around town and past my school, I was there with the
cable release from the camera, clicking away at roughly once a second. I
remember dad had to put an elastic band round the normal shutter release
to half-press it to turn on the exposure meter without setting the film
running at normal 18 or 25 fps. At one point during the journey there was
a ping and the band slipped off, so several seconds of the film are very
over-exposed until he stopped and sorted it out! From the fact that we
drove along a road that was pedestrianised a year or so later, we can date
the film to 1973 or 1974. Interesting to see what's changed and what's
http://youtu.be/f3eZB2QNvtM
Maybe some time when we get our car dashcam, I'll drive as much of the
route as I can to do a comparison film, if I find myself over that way.
Somewhere in among the films that we got digitised a few years ago is one
that dad made, either with that Super 8 camera or else with an older
Standard 8 camera, using stop motion where he animated some of my Dinky
toys driving along a toy road. Nowadays it would be easy with a video
camera or even a still camera to take a series of still photos and animate
them together into a video - and without needing a bright Photoflood light
indoors, too!

I quite enjoyed watching your film. All the roads seem fairly deserted - I
thought at first it must have been on a Sunday, until the bit in town with
the shops. The inevitable jerkiness didn't bother me at all. Any attempt to
blend each picture into the next over several frames would not give a good
result.

[NY]

Post by Dave W
I quite enjoyed watching your film. All the roads seem fairly deserted - I
thought at first it must have been on a Sunday, until the bit in town with
the shops. The inevitable jerkiness didn't bother me at all. Any attempt
to blend each picture into the next over several frames would not give a
good result.

It was shot on a Saturday afternoon (I went to school on a Saturday morning,
but got Wednesday afternoon off, ostensibly to play sport) so you'd expect
the shops and the shopping streets to be heaving. It is scary looking back
to see how quiet the roads were. There's a couple of examples of really bad
driving: the blue Datsun that overtakes the tractor and trailer on the S
bend outside Sandal Motors garage at about 0:30 into the path of the
oncoming white car (mind you, I'm not sure I'd have overtaken the tractor a
few seconds later where my dad does till I could see that the road was
clear) and then the pushy beige Hillman Hunter at 1:30 who swerves onto the
wrong side of the road (and only just avoids the traffic bollard in the
middle of the road immediately afterwards) to avoid the Granada that's in
the middle of the road pulling out from the side road on the left. Bad
driving is not a new phenomenon!

I experimented with blending either two or three adjacent frames and
although it made things smoother, it created very noticeable artefacts such
as ghost images of street lights. Horrible!

Shame we didn't have enough film to shoot a bit on the motorway - now that
really would have been scary at about 8x real life speed.