关于下载jpg格式图片，实际为png格式问题

[Goodboy-dai]

这是我的配置文件：
[app]
version = "v 0.1.0"
title = "MapCloud Tiler"
[output]
#can be mbtiles/file
format ="file"
#the output dir
directory ="output"
[task]
#number of fetchers
workers = 3
#number of savers
savepipe = 1
#min request interval, a speed limit, unit millisecond
timedelay = 50

[tm]
#name for mbtiles
name = "gaode_vec_shanghai_test01_1"
#max and min level for mbtiles
min = 0
max = 11
#can be pbf/png/jpg
format = "jpg"
#can be xyz/tm
schema = "xyz"
#the vector tiles metadata tilejson
# json = ""
#url is the schema url of tiles
# url = "https://api.mapbox.com/v4/mapbox.mapbox-streets-v8/{z}/{x}/{y}.vector.pbf?sku=1016gFniej06a&access_token=pk.eyJ1IjoibWFwYm94IiwiYSI6ImNpejY4M29iazA2Z2gycXA4N2pmbDZmangifQ.-g_vE53SD2WrJ6tFX7QHmA"
# url = "https://api.mapbox.com/v4/mapbox.mapbox-terrain-v2/{z}/{x}/{y}.vector.pbf?sku=1016gFniej06a&access_token=pk.eyJ1IjoibWFwYm94IiwiYSI6ImNpejY4M29iazA2Z2gycXA4N2pmbDZmangifQ.-g_vE53SD2WrJ6tFX7QHmA"
# url = "https://api.maptiler.com/tiles/v3/{z}/{x}/{y}.pbf?key=KDhMfHvorAFkFe64wlZb"
# url = "http://mt0.google.com/vt/lyrs=s&x={x}&y={y}&z={z}"
url = "https://webrd01.is.autonavi.com/appmaptile?lang=zh_cn&size=1&scale=1&style=7&x={x}&y={y}&z={z}"
# url = "https://wprd01.is.autonavi.com/appmaptile?x={x}&y={y}&z={z}&lang=zh_cn&size=1&scl=1&style=8"
# url = "https://webst01.is.autonavi.com/appmaptile?style=6&x={x}&y={y}&z={z}"
# url = "https://wprd01.is.autonavi.com/appmaptile?x={x}&y={y}&z={z}&lang=zh_cn&size=1&scl=2&style=8&ltype=11"
# url = "https://t0.tianditu.gov.cn/DataServer?T=img_w&x={x}&y={y}&l={z}&tk=75f0434f240669f4a2df6359275146d2"
# url = "https://t0.tianditu.gov.cn/DataServer?T=cia_w&x={x}&y={y}&l={z}&tk=75f0434f240669f4a2df6359275146d2"
# url = "https://t0.tianditu.gov.cn/DataServer?T=vec_w&x={x}&y={y}&l={z}&tk=75f0434f240669f4a2df6359275146d2"
# url = "https://t0.tianditu.gov.cn/DataServer?T=cva_w&x={x}&y={y}&l={z}&tk=75f0434f240669f4a2df6359275146d2"

#lrs can set diff boundaries for diff levels

[[lrs]]

min = 0

max = 5

geojson = "./geojson/global.geojson"

[[lrs]]

min = 6

max = 8

geojson = "./geojson/china.geojson"

[[lrs]]

min = 9

max = 10

geojson = "./geojson/jiangsu.geojson"

[[lrs]]
min = 10
max = 18
geojson = "./geojson/shanghai.geojson"

已明确指出要jpg格式的，但是下载下来看bin文件实际是png格式