| | <<<Back 1 day (to 2018/07/30) | 20180731 |
| raki_ | Export rich black png using Ghostscript | 05:56.42 |
| kens | raki_ : repeating yourself isn't going to get you anywhere. I've asked a number of questions, none of whic you have answered. Until you do, nobody can help you further. | 06:56.00 |
| chrisl | Well, rich black with RGB would be a neat trick...... | 07:11.18 |
| kens | Yeah I've already asked him what he's talkign about | 07:11.33 |
| | He doesn't answer, just keeps issuing the same statement | 07:11.57 |
| | Grr why is my text underlined ? | 07:12.12 |
| | Oh now it isn't.... | 07:12.17 |
| funnyimp | hi2all | 07:15.18 |
| sharmi | gs -dSAFER -dBATCH -dNOPAUSE -q -sDEVICE=pngalpha -r360 -dDownScaleFactor=3 -dTextBlackPt=10 -dBlackPtComp=10 -sOutputFile="/Users/rakesh/Desktop/output/c02f010.png" "/Users/rakesh/Desktop/Input/c02f010.pdf" | 09:28.11 |
| | whats wrong with above script | 09:28.29 |
| kens | Well, firstly that's not a script | 09:28.50 |
| sharmi | i couldnt able to maintain rich black in png | 09:28.54 |
| kens | Its a Ghostscript command line | 09:29.00 |
| sharmi | sorry commang | 09:29.10 |
| | command | 09:29.14 |
| kens | Secondly pngalpha doens't support -dDownscaleFacotr as far as I'm aware | 09:29.14 |
| | Thirdly -dTextBlackPt isn't a Ghostscript command line switch as far as I know | 09:29.39 |
| | Finally, what do you think you mean when you say 'rich black' ? | 09:29.56 |
| | BlackPtComp takes either a 0 or a 1, not 10 | 09:31.06 |
| | Also, BlackPtComp only has any effet if you also specify an ICC Profiel to use, by specifying -sOutputICCProfile | 09:32.01 |
| | Randomly stabbing at command line parameters, or making them up, isn't going to get you very far. | 09:32.18 |
| | OK so there is a TextBlackPt buried in the ICC colour management | 09:32.52 |
| | It specifies whether Black Point Cmpensation should be applied to text objects, again it only takes a 0 or a 1, not a 10, and again only has any effect if you specify a ICC profile, which you haven't done. | 09:33.59 |
| chrisl | sharmi: To be clear: "Rick black" refers to mixing CMY components with the K in a CMYK device produce an (allegedly) deeper black. PNG is only ever RGB, it does not support CMYK. | 10:02.42 |
| sharmi | how to improve my quality of image without increasing resolution | 10:03.42 |
| | png image | 10:04.12 |
| kens | You haven't given us an exampe to look at, you havenm't clearly defined what you mean by 'improve' and you;ve rejected the two attempts we've made to give suggestions without any useful comments. | 10:05.31 |
| | And you keep switching the subject. | 10:05.41 |
| chrisl | Given that image quality generally means either "more dots" or "more colors", you're going to have to be more specific about what you mean by "quality". | 10:05.49 |
| kens | We ask about quality and you talk about rich black, we ask about rich black and you tal about quality. | 10:06.01 |
| | sharmi : You need to start answering our questions, or we cannot help you | 10:06.14 |
| sharmi | i mean quality as png image | 10:07.59 |
| kens | yeah that doesn't mean anything | 10:08.11 |
| | What do you perceive as being the problem ? Where can we get an example to look at to see what you mean ? | 10:08.31 |
| sharmi | gs -dSAFER -dBATCH -dNOPAUSE -q -sDEVICE=pngalpha -r120 -sOutputFile="/Users/rakesh/Desktop/output/c02f010.png" "/Users/rakesh/Desktop/Input/c02f010.pdf" | 10:09.04 |
| kens | sharmi you've already given us a command line | 10:09.15 |
| | We need to see th einput file | 10:09.20 |
| | "the input file" | 10:09.27 |
| sharmi | this is the command i am using | 10:09.33 |
| kens | Ye s we know that | 10:09.38 |
| | Where is the inptu file ? | 10:09.42 |
| | Then we cna render it an dlook at it, and **perhaps** we can see what your problem is | 10:09.55 |
| | You need to put the file co2f010.pdf somewhere public so we can try it ourselves | 10:10.48 |
| sharmi | https://wetransfer.com/downloads/aa31f4957015ee447443b18d50de408e20180731101049/4f61ba2b954d9b27e91562a84656802120180731101049/109d60 | 10:11.20 |
| | please use above link to download my input file | 10:11.56 |
| kens | OK now what do you think is the problem ? | 10:13.16 |
| sharmi | https://wetransfer.com/downloads/9fb658179a2a9200e725d25eb087c9c020180731101324/3000775e357bad6afe1d8b6e9f662f1820180731101324/532fef | 10:14.34 |
| | i have given my output on the above link | 10:15.01 |
| kens | Indeed, now what's the problem ? | 10:15.14 |
| chrisl | It looks like I expect it to | 10:15.24 |
| kens | Me too | 10:15.30 |
| sharmi | clarity of an image | 10:15.32 |
| kens | Its a small file at low resolution | 10:15.37 |
| sharmi | my expectation is | 10:16.48 |
| | https://wetransfer.com/downloads/ca9bb5453e5bc49e4947ac2251f2de0c20180731101627/44a6881850fdb708897a1abb2279632820180731101627/7dd62a | 10:16.50 |
| chrisl | Ah, then add -dTextAlphaBits=1 -dGraphicsAlphaBits=1 to your command line | 10:17.16 |
| | Thus "-dSAFER -dBATCH -dNOPAUSE -dTextAlphaBits=1 -dGraphicsAlphaBits=1 -q -sDEVICE=pngalpha -r300 ....." | 10:17.32 |
| sharmi | my dimesion size should be retain | 10:18.01 |
| chrisl | Sorry, I meant "-dSAFER -dBATCH -dNOPAUSE -dTextAlphaBits=1 -dGraphicsAlphaBits=1 -q -sDEVICE=pngalpha -r120 ....." | 10:18.18 |
| kens | TextAlphaBits doesn't change the resolution | 10:18.33 |
| | The basic problem is that you have text at 8 points. This means that a M is 1/9th of an inch in height. at 120 dpi that gives you 13 pixels to draw in. And that's for a capital letter. Lower case letters will have even fewer pixels avilaable to draw the character. | 10:21.22 |
| | Another solution is obviously to render to a higher resolution than required and use an image manipulation tool to resize the final image by 1/3 | 10:23.43 |
| sharmi | anybody have any idea? | 10:56.56 |
| kens | Yes, you've now been given three ideas | 10:57.11 |
| | 1) Ue a higher resolution | 10:57.18 |
| | 2) Use a higher resolution but use DownScaleFactor to reduce the final resolution | 10:57.33 |
| | 3) Use -dTextAlphaBits=1 | 10:57.40 |
| sharmi | but my dimension should not increase | 10:57.44 |
| kens | 4) Render to a higher resolution and use an image manipulation tool to redude teh final image. | 10:58.02 |
| | So that's 4 ideas | 10:58.09 |
| sharmi | i am using device as pngalpha will -dDownScaleFactor give any change | 11:01.16 |
| kens | Why don't you just try it and see ? | 11:01.27 |
| sharmi | used -r360 -dDownScaleFactor=3 i got poor quality compare to previous | 11:03.53 |
| chrisl | FWIW, pngalpha defaults Graphics/TextAlphaBits to 4, so you might want to try using -dTextAlphaBits=2 -dGraphicsAlphaBits=2 as well as 1 | 11:04.10 |
| kens | Yeah you keep saying 'poor quality' but you never say what the problem actually is | 11:04.30 |
| | sharmi : You've had 4 solutions, if you don't like any of them then feel free to go off and invent your own. The final one (render to a higher resolution and use another tool to reduce the image resolution) is the most flexible. | 11:05.34 |
| | I feel we've given you ample free support and I don't propose to continue this conversation any further. | 11:05.59 |
| sharmi | thanks a lot for ur support | 11:06.49 |
| sebras | I'll be pushing another set of jbig2dec commits | 11:17.54 |
| | they all cluster well and have been reviewed, and building under windows appears to work fine. :) | 11:18.22 |
| Robin_Watts | sharmi: I don't think pngalpha supports DownScaleFactor. You'd need to use png16m for that. If you're using png16m and DownScaleFactor, do NOT use GraphicsAlphaBits and TextAlphaBits. | 11:53.47 |
| | IF you use -r600 and -dDownScaleFactor=3, then you end up with 200dpi. | 11:54.29 |
| | Forward 1 day (to 2018/08/01)>>> | |
Log of #ghostscript at irc.freenode.net.