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Re: Can MySql database store images?

From	Tim Watts <tw@dionic.net>
Newsgroups	comp.databases.mysql
Subject	Re: Can MySql database store images?
Followup-To	comp.databases.mysql
Date	2011-04-27 16:32 +0100
Organization	A noiseless patient Spider
Message-ID	<hgpl88-ifi.ln1@squidward.dionic.net> (permalink)
References	(10 earlier) <ip7uo6$u89$1@dont-email.me> <ip8gb0$2ni$2@news.albasani.net> <slrnirg20d.2mh.hellsop@nibelheim.ninehells.com> <n3fl88-n0k.ln1@squidward.dionic.net> <slrnirg9ps.2mh.hellsop@nibelheim.ninehells.com>

Followups directed to: comp.databases.mysql

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Peter H. Coffin wrote:

> On Wed, 27 Apr 2011 13:34:31 +0100, Tim Watts wrote:
>> Peter H. Coffin wrote:
>>
>>> On Wed, 27 Apr 2011 08:24:16 +0100, The Natural Philosopher wrote:
>>>> Norman Peelman wrote:
>>>>> Doug Miller wrote:
>>>>>> In article <ip57sl$rc5$1@dont-email.me>, Norman Peelman
>>>>>>> 460 * 5.3kb
>>>>>>>
>>>>>> You wrote above "460 images ... with an average size of 5393kb" .
>>>>>> 5393kb is 5.4 MEGAbytes, not 5.3kb.
>>>>> 
>>>>>   Yes, my fingers were going faster than my brain.
>>>>> 
>>>>> Average of 5393 bytes (5kb)
>>>>> Max of 10240 bytes (10kb)
>>>>> 
>>>>> ...these are small images.
>>>>> 
>>>>> Dump file (w/images) = 29.8MB
>>>>> Dump file zipped = 1.7MB
>>>>> 
>>>>> 
>>>> It is seldom possible to compress images more than they are already
>>>> compressed.
>>>>
>>>> So I still think you have made a mistake.
>>> 
>>> Dump files can (intentionally and with malice aforethought) export
>>> binary columns in hexidecimal text, which is rather compressible. It's
>>> also very safe from things like people fussing with it with text
>>> editors, being copied and pasted into emails for demonstrative purposes,
>>> and other kinds of mistreatment.
>>> 
>>
>> I think the point that is being overlooked, is that the text, whilst
>> compressible, is itself a re-encoding of an already highly compressed bit
>> of data.
> 
> Some parts of the file are highly-compressed data. Well,
> fairly-highly-compressed, anyway. The actual compression used in, for
> example JFIF/.jpeg is Huffman. More of the initial 'compression' in
> those comes from not actual compression but rather lossy tricks to make
> an image that looks about the same as the original to the eye, but isn't
> itself 'compression' in the sense that the data inside itself isn't
> necessarily further incompressible. What this means is that fairly small
> images don't have a lot of "compressed data" in them in the first place,
> and the overhead for graphics with small fields of image data might be
> easily half overhead.
> 
>> if anything, the intermidate text encoding should make things worse
>> overall, not better.
> 
> One would think so at first glance, but text is really easy to compress.
> 
>> We are still talking about 2.2MB compressed image data mixed up with
>> other stuff in an exploded ASCII form being, somehow, recompressed down
>> to a total which is less than the sum of the original images alone.
> 
> That's the key to what I think is happening here. See, one image may be
> compressible for some small gains. But many images, especially with very
> similar information in the overhead portions of the formats, like
> they're mostly all the same sizes, or use similar color pallets, end up
> being compressable by being able to compress duplicate information
> *between* the images as well as within the image itself.
> 
>> It would make me want to double check the dumps to see they really had
>> everything...
> 
> Always a worthwhile step. But if the dump restores okay, the size alone
> isn't necessarily a warning that something else is wrong.
> 

Nice explanation Peter. That makes sense (in particular the commonality 
between images).

Cheers

Tim

-- 
Tim Watts

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Thread

Can MySql database store images? "Robert Crandal" <rcranz143101@gmail.com> - 2011-04-23 23:47 -0700
  Re: Can MySql database store images? "J.O. Aho" <user@example.net> - 2011-04-24 09:23 +0200
    Re: Can MySql database store images? "Robert Crandal" <rcranz143101@gmail.com> - 2011-04-24 01:19 -0700
      Re: Can MySql database store images? "J.O. Aho" <user@example.net> - 2011-04-24 11:13 +0200
  Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-24 11:17 +0100
  Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-24 13:06 +0100
  Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 08:42 -0400
    Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-24 14:45 +0100
      Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 10:27 -0400
        Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-24 19:04 +0100
          Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 14:44 -0400
            Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-24 20:51 +0100
              Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 17:03 -0400
                Re: Can MySql database store images? Hans Castorp <REWYRLXHEGHO@spammotel.com> - 2011-04-24 23:18 +0200
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 19:55 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 08:30 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 06:32 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 12:04 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 07:18 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 13:32 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 09:09 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 14:17 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 19:29 -0400
                Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-25 12:30 +0100
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 13:59 +0100
                Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-25 18:10 +0100
        Re: Can MySql database store images? Norman Peelman <npeelman@cfl.rr.com> - 2011-04-24 16:40 -0400
          Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 17:05 -0400
            Re: Can MySql database store images? Norman Peelman <npeelman@cfl.rr.com> - 2011-04-25 02:57 -0400
              Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 08:59 +0100
                Re: Can MySql database store images? Norman Peelman <npeelman@cfl.rr.com> - 2011-04-25 21:41 -0400
                Re: Can MySql database store images? Norman Peelman <npeelman@cfl.rr.com> - 2011-04-26 06:20 -0400
                Re: Can MySql database store images? dougatmilmacdotcom@example.com (Doug Miller) - 2011-04-26 14:10 +0000
                Re: Can MySql database store images? Norman Peelman <npeelman@cfl.rr.com> - 2011-04-26 22:24 -0400
                Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-27 08:24 +0100
                Re: Can MySql database store images? Norman Peelman <npeelman@cfl.rr.com> - 2011-04-27 06:41 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-27 12:32 +0100
                Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-27 15:07 +0100
                Re: Can MySql database store images? "Peter H. Coffin" <hellsop@ninehells.com> - 2011-04-27 07:11 -0500
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-27 13:34 +0100
                Re: Can MySql database store images? "Peter H. Coffin" <hellsop@ninehells.com> - 2011-04-27 09:25 -0500
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-27 16:32 +0100
      Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 10:28 -0400
        Re: Can MySql database store images? Norman Peelman <npeelman@cfl.rr.com> - 2011-04-24 16:43 -0400
          Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 08:36 +0100
            Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 06:34 -0400
              Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 11:50 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 07:20 -0400
          Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-25 12:42 +0100
    Re: Can MySql database store images? Luuk <Luuk@invalid.lan> - 2011-04-24 16:27 +0200
      Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-24 15:38 +0100
        Re: Can MySql database store images? Luuk <Luuk@invalid.lan> - 2011-04-24 16:41 +0200
        Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-24 19:07 +0100
          Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 14:46 -0400
            Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-24 21:01 +0100
              Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 17:10 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 08:23 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 06:39 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 12:00 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 07:27 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 13:42 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 09:12 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 14:23 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 19:31 -0400
                Re: Can MySql database store images? "Mr. B-o-B" <mr.chew.baka@gmail.com> - 2011-04-25 20:30 -0500
          Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-25 12:21 +0100
            Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 13:46 +0100
      Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 13:23 -0400
        Re: Can MySql database store images? Luuk <Luuk@invalid.lan> - 2011-04-24 20:31 +0200
          Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 14:48 -0400
            Re: Can MySql database store images? Luuk <Luuk@invalid.lan> - 2011-04-24 21:11 +0200
    Re: Can MySql database store images? Axel Schwenke <axel.schwenke@gmx.de> - 2011-04-24 21:24 +0200
      Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 17:34 -0400
        Re: Can MySql database store images? Luuk <Luuk@invalid.lan> - 2011-04-25 12:04 +0200
          Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 06:40 -0400
            Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 11:48 +0100
              Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 07:28 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 13:36 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 09:17 -0400
                Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 14:30 +0100
                Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-25 18:13 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 19:37 -0400
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 19:35 -0400
    Re: Can MySql database store images? "Robert Crandal" <rcranz143101@gmail.com> - 2011-04-24 13:13 -0700
      Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 17:35 -0400
  Re: Can MySql database store images? Axel Schwenke <axel.schwenke@gmx.de> - 2011-04-24 21:29 +0200
    Re: Can MySql database store images? "Robert Crandal" <rcranz143101@gmail.com> - 2011-04-24 14:37 -0700
      Re: Can MySql database store images? Axel Schwenke <axel.schwenke@gmx.de> - 2011-04-25 00:41 +0200
        Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 20:16 -0400
          Re: Can MySql database store images? Axel Schwenke <axel.schwenke@gmx.de> - 2011-04-25 12:12 +0200
            Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 07:31 -0400
        Re: Can MySql database store images? Tim Watts <tw@dionic.net> - 2011-04-25 08:43 +0100
        Re: Can MySql database store images? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-05-01 09:59 +0200
      Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 20:03 -0400
    Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 17:39 -0400
      Re: Can MySql database store images? Axel Schwenke <axel.schwenke@gmx.de> - 2011-04-25 00:46 +0200
        Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-24 20:18 -0400
          Re: Can MySql database store images? Luuk <Luuk@invalid.lan> - 2011-04-25 12:13 +0200
            Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 06:43 -0400
              Re: Can MySql database store images? Luuk <Luuk@invalid.lan> - 2011-04-25 13:40 +0200
                Re: Can MySql database store images? The Natural Philosopher <tnp@invalid.invalid> - 2011-04-25 12:43 +0100
                Re: Can MySql database store images? Jerry Stuckle <jstucklex@attglobal.net> - 2011-04-25 09:19 -0400
                Re: Can MySql database store images? Luuk <Luuk@invalid.lan> - 2011-04-25 16:46 +0200

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