On 3 July 2010 13:59, Thom Brown <thombrown@gmail.com> wrote:
> On 3 July 2010 03:41, Bruce Momjian <bruce@momjian.us> wrote:
>> Peter Eisentraut wrote:
>>> On fre, 2010-07-02 at 22:15 -0400, Bruce Momjian wrote:
>>> > > 500k of source for just half a dozen simple images? There's
>>> > something
>>> > > seriously wrong there. I suspect the PNGs could be compressed a lot
>>> > > more, but right now I'm wondering exactly how verbose the dia
>>> > "source"
>>> > > representation is.
>>> >
>>> > Here is the PNG URL:
>>> >
>>> > http://momjian.us/expire/pgsql-docs/img/
>>> >
>>> > and the dia files:
>>> >
>>> > http://momjian.us/expire/pgsql-docs/dia/
>>>
>>> The dia stuff is XML that should compress well.
>>
>> Gzip takes the dia directory from 526k to 42k. And of course gzip does
>> little for the PNG files.
>>
>
> How configurable is the generation process for these PNGs? It's just
> that they don't appear to be optimised.
>
> For example, pgclient_server.png is created at 75,089 bytes, but can
> be reduced to 15,643 bytes like in the attached file
> (pgclient_server2.png) by using a 16-colour indexed palette.
>
> Thom
>
Being a bit more generous, and using a 32-colour palette, it looks
like it yields a typical saving of 75%
Original images:
40290 file_based_log_shipping.png
54211 hot_standby.png
52400 page_layout.png
75089 pgclient_server.png
49117 pg_dir_layout.png
17692 pg_lines_code.png
41723 pg_standby.png
25135 pitr.png
10946 postgresql_hist.png
34156 streaming_replication.png
68679 tablespaces.png
18197 vacuum.png
TOTAL: 487635 bytes
32-colour palette images (compression %):
10700 file_based_log_shipping2.png (73.44%)
14245 hot_standby2.png (73.72%)
9896 page_layout2.png (81.11%)
13786 pg_dir_layout2.png (81.64%)
6347 pg_lines_code2.png (87.08%)
11211 pg_standby2.png (36.63%)
18173 pgclient_server2.png (56.44%)
7148 pitr2.png (71.56%)
3873 postgresql_hist2.png (64.62%)
8969 streaming_replication2.png (73.74%)
15338 tablespaces2.png (77.67%)
5846 vacuum2.png (67.87%)
TOTAL: 125532 bytes (74.26%)
..just an idea anyway.
Thom
