improper image header error

[doublej74]

just running one of the examples. Am I missing something is the code broken?

[caiguanhao]

Possible reason for this error:

• the convert command -- make sure you have installed ImageMagick correctly
• the file system you're using -- PNG files was created without image headers

[doublej74]

I installed the latest version of ImageMagick on a simple debian 7 server. No rocket science. It just won't work with the latest version of ImageMagick. Which version of ImageMagick did you use originally?

Maybe the cause lies with baidu. When it starts downloading the tiles, sometimes empty png files pop up in the maps directory. When the map is generated (with the errors as the ones in the screenshot above) the done.png looks something like this:

[caiguanhao]

I've tested the examples in the README.md on my Ubuntu 16.04 server and they worked as expected. Do you use Docker? You can use Docker image like this:

FROM alpine:edge
RUN apk add --no-cache bash imagemagick bc wget libpng-dev

Or run these commands one by one:

cd baidu-maps-download
docker run -it --rm -v="$PWD:/bmd" -w="/bmd" alpine:edge sh
apk add --no-cache bash imagemagick bc wget libpng-dev
bash center2pieces.sh 12616085.15, 2628677.18 15 web-alt 1000 1000 | xargs bash pieces2one.sh
exit
# now you should see the file done.png in the maps directory.