mjpeg file

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chrisPyres66
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mjpeg file

Postby chrisPyres66 » Fri Nov 15, 2019 5:45 am

Dear All,

I used the mjpeg function to create a mjpeg file on sdcard.

1 - The mjpeg file has any resolution description in its propriety, and the index should be recreated when reading with VLC.
What is the simple way to have these proprieties and/or this index ?

2 - To see the mjpeg file on sdcard, i have to replug the camera on pc.
Does it exist a way to refresh the openmv disk with a micropython function or something else in place of ?

Thanks,
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iabdalkader
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Re: mjpeg file

Postby iabdalkader » Fri Nov 15, 2019 5:58 am

chrisPyres66 wrote:
Fri Nov 15, 2019 5:45 am
Dear All,

I used the mjpeg function to create a mjpeg file on sdcard.

1 - The mjpeg file has any resolution description in its propriety, and the index should be recreated when reading with VLC.
What is the simple way to have these proprieties and/or this index ?

2 - To see the mjpeg file on sdcard, i have to replug the camera on pc.
Does it exist a way to refresh the openmv disk with a micropython function or something else in place of ?

Thanks,
No you have to reset the camera for the PC to see the changes. unmount/re-mount might work on Linux.
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kwagyeman
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Re: mjpeg file

Postby kwagyeman » Fri Nov 15, 2019 11:55 am

Not sure about the index question. Can you clarify?
Nyamekye,
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chrisPyres66
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Location: France

Re: mjpeg file

Postby chrisPyres66 » Mon Nov 18, 2019 3:39 am

Thanks,

1 - See the joined file to read the text of vlc when i read the mjpeg file.
Note if i use mpg extension, i dont have this problem with the windows player...

2 - i use windows and my idea was to do it with a mycropython function like machine.reset()..
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index.jpg
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iabdalkader
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Re: mjpeg file

Postby iabdalkader » Mon Nov 18, 2019 1:16 pm

chrisPyres66 wrote:
Mon Nov 18, 2019 3:39 am
Thanks,

1 - See the joined file to read the text of vlc when i read the mjpeg file.
Note if i use mpg extension, i dont have this problem with the windows player...

2 - i use windows and my idea was to do it with a mycropython function like machine.reset()..
Yeah I get this message too with VLC, but the video still plays. Not sure how to fix it, if you have a fix for this let me know.
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kwagyeman
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Re: mjpeg file

Postby kwagyeman » Mon Nov 18, 2019 2:16 pm

I probably have to add a chunk to the file that has an index. I don't know what such a chunk looks like however.
Nyamekye,
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chrisPyres66
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Location: France

Re: mjpeg file

Postby chrisPyres66 » Tue Nov 19, 2019 11:33 am

It is weird, because if i see the vlc messages when i open the video file, it is an avi error ????
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vlc_error.JPG
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kwagyeman
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Re: mjpeg file

Postby kwagyeman » Tue Nov 19, 2019 8:27 pm

It's not an error so much as we just don't output a chunk that the software expects. There's no AVI standard so I just tried to do what I could dig up documentation wise.
Nyamekye,

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