php-general Digest 24 Aug 2006 19:52:20 -0000 Issue 4311
Topics (messages 241072 through 241089):
Re: upload image
241072 by: Peter Lauri
241074 by: Mourad Boulahboub
241077 by: Sonja
241080 by: Mourad Boulahboub
How to deal with errors in forms
241073 by: Merlin
241075 by: Mourad Boulahboub
cURL and sending an POST with an @ as first char.
241076 by: Mathijs
241078 by: Mathijs
241081 by: João Cândido de Souza Neto
241083 by: M. Sokolewicz
Copying IPTC data
241079 by: Dotan Cohen
Re: Why small > big?
241082 by: Alex Turner
241084 by: tedd
[EMAIL PROTECTED]
241085 by: Mourad Boulahboub
Re: Downloading of PgSQL data for use local (crappy subject line)
241086 by: Michelle Konzack
creating mailto: URL including 8-bit characters
241087 by: Jim McIntyre
Re: Session / cookie issues
241088 by: Andrew Kreps
241089 by: Dave Goodchild
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----------------------------------------------------------------------
--- Begin Message ---
Maybe this will help you:
$name = mysql_escape_string($_POST['doc_filename'][$key]);
$author = mysql_escape_string($_POST['doc_filename_author'][$key]);
$filename = mysql_escape_string($value);
$filetype = mysql_escape_string($_FILES['doc_attach']['type'][$key]);
$filesize = mysql_escape_string($_FILES['doc_attach']['size'][$key]);
$filedata = addslashes (fread(fopen
($_FILES['doc_attach']['tmp_name'][$key], "r"),
filesize($_FILES['doc_attach']['tmp_name'][$key])));
$Query = "INSERT INTO filestorage (name, author, filename, filetype,
filesize, filedata) VALUES ('$name', '$author', '$filename', '$filetype',
'$filesize', '{$filedata}')";
/Peter
-----Original Message-----
From: Sonja [mailto:[EMAIL PROTECTED]
Sent: Thursday, August 24, 2006 2:38 PM
To: [email protected]
Subject: [PHP] upload image
Hi,
I have problems with uploading image, here is the code
if(isset($_POST['txtTitle']))
{
$albumId = $_POST['cboAlbum'];
$imgTitle = $_POST['txtTitle'];
$imgDesc = $_POST['mtxDesc'];
$images = uploadImage('fleImage', GALLERY_IMG_DIR);
if ($images['image'] == '' && $images['thumbnail'] == '') {
echo "Error uploading file";
exit;
}
$image = $images['image'];
$thumbnail = $images['thumbnail'];
if (!get_magic_quotes_gpc()) {
$albumName = addslashes($albumName);
$albumDesc = addslashes($albumDesc);
$imgPath = addslashes($imgPath);
}
$sql = "INSERT INTO tbl_image (im_album_id, im_title,
im_description,
im_image, im_thumbnail, im_date)
VALUES ($albumId, '$imgTitle', '$imgDesc', '$image',
'$thumbnail',
NOW())";
mysql_query($sql) or die('Error, add image failed : ' . mysql_error());
echo
"<script>window.location.href='index.php?page=list-image&album=$albumId';</s
cript>";
exit;
}
when I upload a picture return me error uploadin image.
Thanks
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--- End Message ---
--- Begin Message ---
Hi sonja,
Sonja schrieb am 24.08.2006 09:38:
> Hi,
>
> I have problems with uploading image, here is the code
>
> if(isset($_POST['txtTitle']))
> {
> $albumId = $_POST['cboAlbum'];
> $imgTitle = $_POST['txtTitle'];
> $imgDesc = $_POST['mtxDesc'];
>
> $images = uploadImage('fleImage', GALLERY_IMG_DIR);
how does the function uploadImage looks like?
> if ($images['image'] == '' && $images['thumbnail'] == '') {
> echo "Error uploading file";
> exit;
> }
the error comes from this if-clause that is depending from the function
above.
regards
Mourad
--- End Message ---
--- Begin Message ---
Hi,
It looks like:
function uploadImage($inputName, $uploadDir)
{
$image = $_FILES[$inputName];
$imagePath = '';
$thumbnailPath = '';
// if a file is given
if (trim($image['tmp_name']) != '') {
$ext = substr(strrchr($image['name'], "."), 1);
// generate a random new file name to avoid name conflict
// then save the image under the new file name
$imagePath = md5(rand() * time()) . ".$ext";
$result = move_uploaded_file($image['tmp_name'], $uploadDir .
$imagePath);
if ($result) {
// create thumbnail
$thumbnailPath = md5(rand() * time()) . ".$ext";
$result = createThumbnail($uploadDir . $imagePath,
$uploadDir .
'thumbnail/' . $thumbnailPath, THUMBNAIL_WIDTH);
// create thumbnail failed, delete the image
if (!$result) {
unlink($uploadDir . $imagePath);
$imagePath = $thumbnailPath = '';
} else {
$thumbnailPath = $result;
}
} else {
// the image cannot be uploaded
$imagePath = $thumbnailPath = '';
}
}
return array('image' => $imagePath, 'thumbnail' => $thumbnailPath);
}
Mourad Boulahboub wrote:
>
> Hi sonja,
>
>
>
> Sonja schrieb am 24.08.2006 09:38:
>> Hi,
>>
>> I have problems with uploading image, here is the code
>>
>> if(isset($_POST['txtTitle']))
>> {
>> $albumId = $_POST['cboAlbum'];
>> $imgTitle = $_POST['txtTitle'];
>> $imgDesc = $_POST['mtxDesc'];
>>
>> $images = uploadImage('fleImage', GALLERY_IMG_DIR);
>
> how does the function uploadImage looks like?
>
>
>> if ($images['image'] == '' && $images['thumbnail'] == '') {
>> echo "Error uploading file";
>> exit;
>> }
>
> the error comes from this if-clause that is depending from the function
> above.
>
> regards
> Mourad
>
> --
> PHP General Mailing List (http://www.php.net/)
> To unsubscribe, visit: http://www.php.net/unsub.php
>
>
>
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--- End Message ---
--- Begin Message ---
Hi Sonja,
Sonja schrieb am 24.08.2006 12:36:
> Hi,
> It looks like:
>
> $result = move_uploaded_file($image['tmp_name'], $uploadDir .
> $imagePath);
is $uploadDir writeable to the webserver!? check this first.
if it is
>
> if ($result) {
> // create thumbnail
> $thumbnailPath = md5(rand() * time()) . ".$ext";
> $result = createThumbnail($uploadDir . $imagePath,
> $uploadDir .
> 'thumbnail/' . $thumbnailPath, THUMBNAIL_WIDTH);
check $uploadDir/thumbnail for permissions. This directory also have to
be writeable.
> if (!$result) {
> unlink($uploadDir . $imagePath);
> $imagePath = $thumbnailPath = '';
in case the thumbnail-directory is not writeable, $imagePath and
$thumbnailPath get blank here
> } else {
> // the image cannot be uploaded
> $imagePath = $thumbnailPath = '';
in case $uploadDir is not writeable, imagePath and $thumbnailPath get
blank here.
so your other script fails here, because it gets nothing back:
> if ($images['image'] == '' && $images['thumbnail'] == '') {
> echo "Error uploading file";
> exit;
> }
you can make troubleshooting by first commenting out the check for
uploaded thumbnail and see if the image get uploaded without
"thumbnailing" it.
regards
Mourad
--- End Message ---
--- Begin Message ---
Hi there,
I do have a form where there is also a field with max 2000 characters
the user can put in.
Now before processing the data with php, I do a checkin the script for
certain criterias if something lookes wrong I do redirect him to the
original form with inserting the data he has entered. I do this via GET
e.g.: ?title=test&body=blablub
That works fine with one exception. If the user does enter 2000
characters (or a lot c.) they do get transfered via URL as well and that
is not possible. Firfox for example then simply displays a blank page!!!
It would be fine if he would return with just a few less characters, but
at least display the error message I am providing.
Now, 2 questions:
1) Does anybody know why firefox is shoing a blank page? If the URL does
contain less characters, lets say 100 everything works fine.
2) How could I possibly save his entry? Maybe with the help of a cookie?
But then, I do redirect to the page. So I do send a header. As far as I
know this only once possible?
For example:
setcookie('bla test');
HEADER("Location:".$data[rurl]."?error=".$error.$parameter);
I would rather not like to use the help of a database.
Any ideas?
Regards,
Merlin
--- End Message ---
--- Begin Message ---
Hi Merlin,
try with sessions. in this case you don't have to append something to
the URL as parameters
Merlin schrieb am 24.08.2006 11:40:
> Hi there,
>
> I do have a form where there is also a field with max 2000 characters
> the user can put in.
>
> Now before processing the data with php, I do a checkin the script for
> certain criterias if something lookes wrong I do redirect him to the
> original form with inserting the data he has entered. I do this via GET
> e.g.: ?title=test&body=blablub
>
> That works fine with one exception. If the user does enter 2000
> characters (or a lot c.) they do get transfered via URL as well and that
> is not possible. Firfox for example then simply displays a blank page!!!
> It would be fine if he would return with just a few less characters, but
> at least display the error message I am providing.
>
> Now, 2 questions:
> 1) Does anybody know why firefox is shoing a blank page? If the URL does
> contain less characters, lets say 100 everything works fine.
> 2) How could I possibly save his entry? Maybe with the help of a cookie?
> But then, I do redirect to the page. So I do send a header. As far as I
> know this only once possible?
> For example:
> setcookie('bla test');
> HEADER("Location:".$data[rurl]."?error=".$error.$parameter);
>
> I would rather not like to use the help of a database.
>
> Any ideas?
>
> Regards,
>
> Merlin
>
--- End Message ---
--- Begin Message ---
Hello there,
I Have a question about cURL and sending POST data.
I have an array with values which are needed for an POST.
There is one value which starts with an @.
This gives me a error: ErrorNo.: 26, ErrorMsg: 'failed creating formpost
data'.
This is becouse an @ at the start of a value is treated as an File
upload or something.
I realy need this to be an @ at the start, and i can't add an space
infront of it.
How can i fix this.
Tryed searching cURL's website didn't found anything (yet).
Thx in advance.
--- End Message ---
--- Begin Message ---
Mathijs wrote:
Hello there,
I Have a question about cURL and sending POST data.
I have an array with values which are needed for an POST.
There is one value which starts with an @.
This gives me a error: ErrorNo.: 26, ErrorMsg: 'failed creating formpost
data'.
This is becouse an @ at the start of a value is treated as an File
upload or something.
I realy need this to be an @ at the start, and i can't add an space
infront of it.
How can i fix this.
Tryed searching cURL's website didn't found anything (yet).
Thx in advance.
It seems that i have found a fix.
I Now check if it starts with an "@" and the replaces it with "\@".
Then it will send normaly :).
If anyone has an other sulution, please tell me.
--- End Message ---
--- Begin Message ---
I think urlencode can solve this.
"Mathijs" <[EMAIL PROTECTED]> escreveu na mensagem
news:[EMAIL PROTECTED]
> Hello there,
>
> I Have a question about cURL and sending POST data.
>
> I have an array with values which are needed for an POST.
> There is one value which starts with an @.
> This gives me a error: ErrorNo.: 26, ErrorMsg: 'failed creating formpost
> data'.
>
> This is becouse an @ at the start of a value is treated as an File upload
> or something.
>
> I realy need this to be an @ at the start, and i can't add an space
> infront of it.
>
> How can i fix this.
> Tryed searching cURL's website didn't found anything (yet).
>
> Thx in advance.
--- End Message ---
--- Begin Message ---
Mathijs wrote:
Mathijs wrote:
Hello there,
I Have a question about cURL and sending POST data.
I have an array with values which are needed for an POST.
There is one value which starts with an @.
This gives me a error: ErrorNo.: 26, ErrorMsg: 'failed creating
formpost data'.
This is becouse an @ at the start of a value is treated as an File
upload or something.
I realy need this to be an @ at the start, and i can't add an space
infront of it.
How can i fix this.
Tryed searching cURL's website didn't found anything (yet).
Thx in advance.
It seems that i have found a fix.
I Now check if it starts with an "@" and the replaces it with "\@".
Then it will send normaly :).
If anyone has an other sulution, please tell me.
it's called "escaping meta-characters", @ has a special meaning, \@ (the
escaped version of @) is the literal @ character. the same way as ' in
many languages is also a special character, \' is its counterpart, the
literal quote.
So, no, there shouldn't be "another solution" since your solution is the
correct one.
- tul
--- End Message ---
--- Begin Message ---
I have a bunch of pictures that I need to copy IPTC data from one
field to another. I can read the first field (#118) with iptcparse,
but I cannot get iptcembed to write to the second field (#025). The
manual says "This function is currently not documented; only the
argument list is available." and the comments were not enough to get
me moving. Could someone provide a working example of writing to a
single IPTC field with iptcembed? I'm sure that I could pick it up
from there. Thanks.
Dotan Cohen
http://what-is-what.com
--- End Message ---
--- Begin Message ---
As I promised, here is the writeup with examples:
http://nerds-central.blogspot.com/2006/08/choosing-file-format-for-small-web.html
Cheers
AJ
tedd wrote:
Alex:
Excuse for top posting:
You said: Clear as mud?
Well actually, it's simperer than I thought. After your reply, I did
some reading on jpeg and found it's simply a transform, not unlike FFT
where two-dimensional temporal data is transformed from the time domain
to the frequency domain -- very interesting reading.
The reverse cosine matrix you mention is probably the discrete cosine
transform (DCT) matrix where the x, y pixels of an image file have a z
component representing color. From that you can translate the data into
the frequency domain, which actually generates more data than the original.
However, the quality setting is where you make it back up in compression
ratio's by trimming off higher frequencies which don't add much to the
data. Unlike the FFT, the algorithm does not address phasing, which I
found interesting.
However, the answer to my question deals with the quality statement. In
the statement:
imagejpeg($image_p, null, 100);
I should have used something less than 100.
I've change the figure to 25 and don't see any noticeable difference in
quality of the thumbnail.
It seems to me there should be a table (or algorithm) somewhere that
would recommend what quality to use when reducing the size of an image
via this method. In this case, I reduced an image 62 percent (38% of the
original) with a quality setting of 25 and "see" no difference. I think
this (the quality factor) is programmable.
As for png images, I would probably agree (if I saw comparisons), but
not all browsers accept them. I belive that at least one IE has problems
with png's, right?
tedd
At 4:45 PM +0100 8/23/06, Alex Turner wrote:
M Sokolewice got it nearly correct. However, the situation is a
little more complex than he has discussed.
The % compression figure for jpeg is translated into the amount of
information stored in the reverse cosine matrix. The size of the
compressed file is not proportional to the % you set in the
compressor. Thus 100% actually means store all the information in the
reverse cosine matrix. This is like storing the image in a 24 bit
png, but with the compressor turned off. So at 100% jpeg is quite
inefficient.
The other issue is the amount of high frequency information in your
images. If you have a 2000x2000 image with most of the image dynamics
at a 10 pixel frequency, and you reduce this to 200x200 then the JPEG
compression algorithm will 'see' approximately the same amount of
information in the image :-( The reality is not quite as simple as
this because of the way JPEG uses blocks etc, but it is an easy way of
thinking about it.
What all this means is that as you reduce the size of an image, if you
want it to retain some of the detail of the original but at a smaller
size, there will be a point at which 8 or 24 bit PNG will become a
better bet.
Clear as mud?
AJ
M. Sokolewicz wrote:
I'm not quite sure, but consider the following:
Considering the fact that most JPEG images are stored with some form
of compression usually ~75% that would mean the original image, in
actual size, is about 1.33x bigger than it appears in filesize. When
you make a thumbnail, you limit the amount of pixels, but you are
setting compression to 100% (besides that, you also use a truecolor
pallete which adds to its size). So, for images which are scaled down
less than 25% (actually this will prob. be more around 30-ish, due to
palette differences) you'll actually see the thumbnail being bigger
in *filesize* than the original (though smaller in memory-size)
- tul
P.S. isn't error_reporting( FATAL | ERROR | WARNING ); supposed to be
error_reporting( E_FATAL | E_ERROR | E_WARNING ); ??
tedd wrote:
Hi gang:
I have a thumbnail script, which does what it is supposed to do.
However, the thumbnail image generated is larger than the original
image, how can that be?
Here's the script working:
http://xn--ovg.com/thickbox
And, here's the script:
<?php /* thumb from file */
/* some settings */
ignore_user_abort();
set_time_limit( 0 );
error_reporting( FATAL | ERROR | WARNING );
/* security check */
ini_set( 'register_globals', '0' );
/* start buffered output */
ob_start();
/* some checks */
if ( ! isset( $_GET['s'] ) ) die( 'Source image not specified' );
$filename = $_GET['s'];
// Set a maximum height and width
$width = 200;
$height = 200;
// Get new dimensions
list($width_orig, $height_orig) = getimagesize($filename);
if ($width && ($width_orig < $height_orig))
{
$width = ($height / $height_orig) * $width_orig;
}
else
{
$height = ($width / $width_orig) * $height_orig;
}
// Resample
$image_p = imagecreatetruecolor($width, $height);
$image = imagecreatefromjpeg($filename);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height,
$width_orig, $height_orig);
// Output & Content type
header('Content-type: image/jpeg');
imagejpeg($image_p, null, 100);
/* end buffered output */
ob_end_flush();
?>
---
Thanks in advance for any comments, suggestions or answers.
tedd
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--- End Message ---
--- Begin Message ---
Alex:
Apologies again for top-posting.
No problem with the "sloppy" language, it was more than good enough
to get your idea across. Besides, I always hate being called for
using a term incorrectly when I actually knew better.
My claim that the quality-value term can be computed is not as
involved as you describe. I was simply meaning that IF one used the --
imagejpeg($image_p, null, 100);
-- statement for the sole purpose of making a thumbnail from a larger
image, then there should be a correlation between size before/after
and the "quality-term".
For example, if I take an image and simply shrink it to 1/4 it's
size, then I should be able to show the image using 1/4 as many
pixels without much loss in quality. Now, how I decide which pixels
are representative of their local pixel groups in sampling, is
another thing and I leave that to the JPEG algorithm.
Considering in this thread where I left the quality at 100% and
reduced the image to less 40 percent of the original, and the end
result was that I actually made a larger file. So, I belive that at
least this example shows that 100% is not a good quality value
setting for reducing images -- thus we know the high end is less than
100.
Clearly as one reduces images, the quality-value required should also
reduce. Now, my gut feeling is that this value in reduction is
predictable, perhaps linear, perhaps polynomial, perhaps something
that would lend itself well to fuzzy logic -- I don't know
specifically what that may be, but I believe it can be programmed.
That's what I was addressing. I have NO data to back-up my gut
feeling.
As for your other comments regarding blocks and edge effects
(mosquito noise) they have direct counterparts in temporal signal
processing -- trying to truncate any signal is going to introduce
noise.
That's the reason for so many filter taper solutions, such as cosign,
hamming, hanning, and more than I wish to remember. I've done a
considerable amount of that type of programming.
Your comments about the visual aspects of the brain are right-on and
I find that investigation fascinating. There is so much to learn and
so much to gain by understanding how we process data (visual and
otherwise).
Your comments about tonally rich areas of the face being more
addressed by the brain is true, but the reason for this is two fold:
one, it is more complicated; but two, it's a face! Our brains process
images differently for different objects. Turn a picture of someone's
face upside down and our brains don't process the image the same.
Interesting, huh?
In any event, (back on topic as you say) our brains process images
much differently than what a compression algorithm could address. On
one hand, it has to reduce the image in areas where the brain is not
interested, and on the other hand, it has to retain those visual
aspects that the brain is built to recognize. That's not doable
without error unless the algorithm mimics the brain.
But, in general terms (baring brain specific variations), as an image
is reduced, one should be able to reduce the value of the quality
term in some predictable manner depending upon the ratio of change.
True or not, that's my claim.
Thanks for the exchange -- it was interesting.
tedd
---
At 11:07 PM +0100 8/23/06, Alex Turner wrote:
Tedd,
Sorry for the floppy language. You are quite correct, the name is
discrete cosine. I get too relaxed sometimes.
As to the visual impact of a degree of compression, I don't think
that you can automate this. The issue surrounds the way the brain
processes information. When you see something, you brain processes
the visual field and looks for patters that it recognizes and then
your conscious mind becomes aware of the patterns, not actually the
thing you are looking at. Optical illusions can illustrate this
point. For example where you see a bunch of blobs on a white
background and then someone tells you it is a dog and you see the
dog. Once you see the dog you can no longer 'not see it'. This is
because of the way the brain processes patterns.
The trick to DCT is that in most 'organic' images - people, trees
etc - the patterns for which your brain is looking actually occupy
low frequencies. However, the majority of the information which is
encoded into the image is in high frequencies. Consequently, by
selectively removing the high frequencies, the image appears to the
conscious mind to be the same whilst in reality it is degraded.
The snag come when the pattern your brain is looking to match to
requires high frequencies. The classic is a edge. If one has an
infinitely large white background with a single infinitely sharp
line on it, you require infinite frequencies to encode it correctly
(ten years ago I knew the proof for this, time and good wine has put
a stop to that). This is much like the side band problem in radio
transmission. If you encode an image in dimensional space rather
than in frequency space you don't get this problem (hence PNG
permitting perfectly sharp lines).
So - back on topic. If you take an image with sharp lines in it,
then pass it through DCT twice (the process in symmetrical) but
loose some of the high frequency data in the process (compression)
then the result is that the very high frequency components that
encode the edge are stripped off. Rather than (as one might like)
this making the edge fussy, it produces what is called mosquito
noise around the edges.
Because mosquito noise is nothing like what you are 'expecting' to
see, the brain is very sensitive to it.
Thus, the amount you notice the compression of JPEG depends on the
nature of the image you compress.
Now it gets nasty. DCT scales as a power of n (where n is the size
of image) - there is a fast DCT process like the F in FFT. But it
is still non linear. This means that to make the encoding and
decoding of JPEG reasonably quick the image is split into blocks and
each block is separately passed through the DCT process. This is
fine except that it produces errors from one block to the next as to
where the edges are in HSV space. Thus, as the compression is
turned up, the edges of the block can become visible due to
discontinuities in the color, huge and saturation at the borders.
This again is sensitive to the sort of image you are compressing.
For example, if it has a very flat (say black or white) background,
then you will not notice. Alternatively, if the image is tonally
rich, like someone's face, you will notice it a lot.
Again, this effect means that it is not really possible to automate
the process of figuring out what compression setting is optimum.
As for PNG: As far as I know, the only issue with any realistic
browser (other than very old ones like IE2 or something) is that the
alpha channel is not supported. As there is no alpha channel in
JPEG, so there is no difference. Though I do not profess to be
absolutely sure that all browsers you might encounter manage PNG ok.
Side Issues:
DCT is integer. This means that if you have zero compression in the
DCT process, then you get out what you put in (except if you get
overflow, which can be avoided as far as I know). This is not the
case in FFT where floating point errors mean you always loose
something. Thus JPEG/100% should be at or near perfect (lossless)
but does not actually compress.
Another area where FFT and DCT become very interesting is in moving
picture processing. You can filter video using FFT or DCT in ways
that are hard or impossible using spacing filters. This can be good
for improving noisy or fussy 'avi' files etc.
Best wishes
AJ
PS - I'll stick the above on my nerd block
nerds-central.blogspot.com, if you have any good links to suggest to
expand the subject, please let me know and I shall add them.
Alexander J Turner Ph.D.
www.project-network.com
www.deployview.com
www.funkifunctions.blogspot.com
-----Original Message-----
From: tedd [mailto:[EMAIL PROTECTED]
Sent: 23 August 2006 20:17
To: Alex Turner; [email protected]
Subject: TPN POSSIBLE SPAM:[PHP] Re: Why small > big?
Alex:
Excuse for top posting:
You said: Clear as mud?
Well actually, it's simperer than I thought. After your reply, I did
some reading on jpeg and found it's simply a transform, not unlike
FFT where two-dimensional temporal data is transformed from the time
domain to the frequency domain -- very interesting reading.
The reverse cosine matrix you mention is probably the discrete cosine
transform (DCT) matrix where the x, y pixels of an image file have a
z component representing color. From that you can translate the data
into the frequency domain, which actually generates more data than
the original.
However, the quality setting is where you make it back up in
compression ratio's by trimming off higher frequencies which don't
add much to the data. Unlike the FFT, the algorithm does not address
phasing, which I found interesting.
However, the answer to my question deals with the quality statement.
In the statement:
imagejpeg($image_p, null, 100);
I should have used something less than 100.
I've change the figure to 25 and don't see any noticeable difference
in quality of the thumbnail.
It seems to me there should be a table (or algorithm) somewhere that
would recommend what quality to use when reducing the size of an
image via this method. In this case, I reduced an image 62 percent
(38% of the original) with a quality setting of 25 and "see" no
difference. I think this (the quality factor) is programmable.
As for png images, I would probably agree (if I saw comparisons), but
not all browsers accept them. I belive that at least one IE has
problems with png's, right?
tedd
At 4:45 PM +0100 8/23/06, Alex Turner wrote:
M Sokolewice got it nearly correct. However, the situation is a
little more complex than he has discussed.
The % compression figure for jpeg is translated into the amount of
information stored in the reverse cosine matrix. The size of the
compressed file is not proportional to the % you set in the
compressor. Thus 100% actually means store all the information in
the reverse cosine matrix. This is like storing the image in a 24
bit png, but with the compressor turned off. So at 100% jpeg is
quite inefficient.
The other issue is the amount of high frequency information in your
images. If you have a 2000x2000 image with most of the image
dynamics at a 10 pixel frequency, and you reduce this to 200x200
then the JPEG compression algorithm will 'see' approximately the
same amount of information in the image :-( The reality is not
quite as simple as this because of the way JPEG uses blocks etc, but
it is an easy way of thinking about it.
What all this means is that as you reduce the size of an image, if
you want it to retain some of the detail of the original but at a
smaller size, there will be a point at which 8 or 24 bit PNG will
become a better bet.
Clear as mud?
AJ
M. Sokolewicz wrote:
I'm not quite sure, but consider the following:
Considering the fact that most JPEG images are stored with some
form of compression usually ~75% that would mean the original
image, in actual size, is about 1.33x bigger than it appears in
filesize. When you make a thumbnail, you limit the amount of
pixels, but you are setting compression to 100% (besides that, you
also use a truecolor pallete which adds to its size). So, for
images which are scaled down less than 25% (actually this will
prob. be more around 30-ish, due to palette differences) you'll
actually see the thumbnail being bigger in *filesize* than the
original (though smaller in memory-size)
- tul
P.S. isn't error_reporting( FATAL | ERROR | WARNING ); supposed to
be error_reporting( E_FATAL | E_ERROR | E_WARNING ); ??
tedd wrote:
Hi gang:
I have a thumbnail script, which does what it is supposed to do.
However, the thumbnail image generated is larger than the original
image, how can that be?
Here's the script working:
http://xn--ovg.com/thickbox
And, here's the script:
<?php /* thumb from file */
/* some settings */
ignore_user_abort();
set_time_limit( 0 );
error_reporting( FATAL | ERROR | WARNING );
/* security check */
ini_set( 'register_globals', '0' );
>>>
/* start buffered output */
ob_start();
/* some checks */
if ( ! isset( $_GET['s'] ) ) die( 'Source image not specified' );
$filename = $_GET['s'];
// Set a maximum height and width
$width = 200;
$height = 200;
// Get new dimensions
list($width_orig, $height_orig) = getimagesize($filename);
if ($width && ($width_orig < $height_orig))
{
$width = ($height / $height_orig) * $width_orig;
}
else
{
$height = ($width / $width_orig) * $height_orig;
}
// Resample
$image_p = imagecreatetruecolor($width, $height);
$image = imagecreatefromjpeg($filename);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height,
$width_orig, $height_orig);
// Output & Content type
header('Content-type: image/jpeg');
>>>imagejpeg($image_p, null, 100);
/* end buffered output */
ob_end_flush();
?>
---
Thanks in advance for any comments, suggestions or answers.
tedd
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--- Begin Message ---
news.gmane.org
--- End Message ---
--- Begin Message ---
Hello Richard,
Am 2006-08-18 14:02:51, schrieb Richard Lynch:
> For LARGE datasets, CSV or tab-delimited transfers are probably going
> to be easiest to suck in to the DB.
No, they are only one ore more rows (~1-20) from the
"timeline_table" and the a row from the "projects_table"
> Another option is to just use pg_dump, if you want whole tables.
10 GByte is a little to much for little $USER. ;-)
> Otherwise, honestly, I'd suggest you just export your data to RSS or
> XML and let the user choose how to open it up.
Hmmm, I have no experience with RSS or XML. Do you have links?
And the, "let the user choose how to open it up" - ROTFL!!!
The $USER is the Typical OFFICE-Guy with ZERO clue about informatic
His/Her workstation has all installed to handel the downloads,
since ist a full Intranet system pased on PHP5.
> Even CSV export is better than PHP arrays, since they can open the
> stuff up in Excel if they want to.
Excel? -- LOL, ROTFL!!!
Micosuck-Ware was droped for some (3) years!
Since we have encountered the Windows is calling home without the
$USER knowledge and since I am working for the Ministry of Defense...
Greetings
Michelle Konzack
Systemadministrator
Tamay Dogan Network
Debian GNU/Linux Consultant
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##################### Debian GNU/Linux Consultant #####################
Michelle Konzack Apt. 917 ICQ #328449886
50, rue de Soultz MSM LinuxMichi
0033/6/61925193 67100 Strasbourg/France IRC #Debian (irc.icq.com)
--- End Message ---
--- Begin Message ---
Hi,
I'm trying to create a mailto: link in a page that will fill in the
Subject and Bopy of a new email message with Spanish-language text.
The text lives in strings in an array of localized text. Accented
characters in the text are encoded as HTML entities. So, for example,
the subject and body text might look like this in the raw data:
$subject = 'Art&iculo acerca de Spyware';
$body = 'Creo que te será de interés este artíulo...';
I can't figure out how to URL encode the characters so they work
properly when the email link is created. I tried:
$encSubject = rawurlencode(html_entity_decode($subject));
$encBody = rawurlencode(html_entity_decode($body));
echo '<a href="mailto:?subject=' . $encSubject . "&body=" . $encBody . (etc.)
but that didn't work. The accented characters show up as empty
squares in the email.
I also tried adding various charset parameters to html_entity_decode,
but that didn't work either:
$encSubject = rawurlencode(html_entity_decode($subject), ISO-8859-1);
What does appear to work is simply not encoding the text at all, but
that leaves a bunch of spaces and ampersand characters in the URL,
and that's not supposed to be done.
I'd appreciate the list's help figuring out how to do this. Many thanks!
-Jim
--- End Message ---
--- Begin Message ---
Could it be a 3rd party cookie problem? Does IE display the little
eyeball privacy icon on the troubled user's browser status bar? I
seem to remember having issues when Microsoft started supporting the
cookie privacy stuff.
On 8/23/06, Dave Goodchild <[EMAIL PROTECTED]> wrote:
Hi all. I mailed some time ago regarding a cookie/session issue I am having
and thank you all for your useful and knowledgeable responses. I have now
used 10 separate testers and 9 are able to progress through a 3-stage form
process that validates data as it goes along and enters the data into the
session array - enabling the user to go back and see previous forms
pre-populated with their selected data (cahcing is enforced on these pages).
However, the client still has issues and I have confirmed that their browser
is rejecting cookies. They are using IE on Win XP and have Internet security
set to Medium. I set mine to the same, used IE to go through the process and
had no such issues. Can anyone tell me if I am missing something obvious?
--
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http://www.projectkarma.co.uk
--- End Message ---
--- Begin Message ---
On 24/08/06, Andrew Kreps <[EMAIL PROTECTED]> wrote:
Could it be a 3rd party cookie problem? Does IE display the little
eyeball privacy icon on the troubled user's browser status bar? I
seem to remember having issues when Microsoft started supporting the
cookie privacy stuff.
I will check thanks - the user does not seem to have issues using other
cookie-driven sites.
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http://www.projectkarma.co.uk
--- End Message ---
