Sunday, 28 April 2013

Google Analytics Report

This report is feedback on the information that Google analytics provide about my blog. Such as how many of the people visiting my blog are new or returning, the web browser they use, what language they speak and where they come from.

It was shown from blogger and Google analytics that the most viewed post was week two. This post was about privacy. This post also has the most comments. It contains 26 page views. The main reason for this being the most viewed is the fact that ten people had to read the post and leave feedback on it. Google Analytics also provides information that visitors spent 22 seconds on this post.

The common source of traffic was from and 105 page views came from; this is where most users would find this blog. The other referring sites come from blogs in my class to which my blog is linked too. There are no stats provided for the search words used to find my blog mainly because this blog is found through other blogs that it is linked too.Also, there is no data on search words for this blog. One there is not enough people visiting this blog and secondly, the only people visiting this site are fellow students in my class. There is no to search for this blog. 

It is shown by Google Analytics that Google Chrome was the most popular browser to the view the blog with.42.68% .The second most popular browser was Firefox with 33.12% and third was Internet explorer with 15.92% of the share. It also stated that users using Chrome and Firefox stayed on the blog for an average of around four minutes. Search for this blog. 

Unlike the browsers, there is little diversity when it comes to operating systems used to look at this blog. The most popular operating system was Windows with 94.27% of the second was Macintosh with 5.10% of the visits. This is not much of a surprise when the computers in the student labs we use are windows and very people in our course have Apple computers.

The ratio of new visits to returning visitors is 3:2.Where new visitors is 57,32% of the visits and returning visitors is 42.68% .I believe this accounts for the people in my class looking at my blog for feedback or curiousness. Whereas the users who don't return are bots or outside users of my course who accidently viewed by blog.

Other information, I would like to include is the language and the location of the visitors to my blog. The most popular language was English. This makes sense as the posts were written in English. Secondly the location of the users was Ireland which had 155 visits to the blog. There were also two visits from America; I account these visits as bots. From January to the end of April, this blog was visited 157 times with 666 page views .However; there were only 90 unique visitors. The average visit was 3 minutes long, with 4 pages being viewed on average by each user. This makes sense when feedback was given by reading through a couple posts.

Week 11

This week it was discussed in greater detail Google Analytics. It shows greater in depth information provided than by this blog. It was discussed the importance of this information, knowing which webpage on your website or what article is getting the most visits, or are visitors returning often. This is important information for any business or web developer.
In the second lecture, search engine optimization (S.E.O) was discussed again.
Our lab this week was cancelled. However, I took this time to finish my third assignment, my essay on piracy vs. privacy. I made sure the essay was referenced properly and the grammar was correct.
This is my final blog. I have written a blog every week from January to February. Overall, I have enjoyed the experienced. It became part of my routine for the week to write about what we covered in web publishing.


Thursday, 18 April 2013

Image Report- size and quality in JPEG and GIF images

Introduction:trade-off between size and quality in JPEG and GIF images

For this report, I had to download three images and experiment with these images in the JPEG and GIF format, look at the relationship between image qualities and file size. When looking at the images in the GIF format, I had to look at effects of the image with and without dithering .Also had to draw conclusions from the data such as which number of colours provides the best value and what is the lowest acceptable numbers of colours. I used Adobe Photoshop version: 13.0.


                                                           original image

                                                      original image png

                                              JPEG format

image 1 JPEG 100%


                                                                         best value

The Image providing the best value is the image with 60 % of it colours. There is very little difference between the image with 100% of its colour palette and 60%.It does not lose any of its sharpness. Another reason for choosing this image is the file size. The image at 60% is only 77KB whereas the image at 100% is 276 KB. It becomes pointless and redundant to pick the image at 100%, when there is no real advantage. Especially, regards to image compression for the web.

                                                                  image 1 JPEG 60%

                                              Lowest acceptable Quality

                The lowest quality that is acceptable is the image that contains 30% of its colour palette.When you start to go lower than 30%, it starts to loose its sharpness.It looses it brightnes and starts to become darker until it looses all resemblence to the original image.
                                                                           image 1 JPEG 30%

The graph below shows the image quality versus the file size. It shows that the quality of the image is directionally proportional to size of the file. This is important when compressing the image. At what point does the image become redundant.


GIF format


best value

The Image below presents the best value of the image, which contains 128 colours with dithering. I choose this option as the clouds looked saturated and grainy when compressed, using the other options. The size of this file is 156 KB. This is good value when you consider that this image at max resolution without dithering is 177 Kb and with dithering is 194 KB.
                                                               image 1 GIF(128) with dither

Lowest acceptable Quality
The lowest quality that is acceptable is this image which contains 64 colours with dithering. The other resolutions lose all of their colour and sharpness.

                                                                 image 1 GIF(64) with dither

  These two graphs compare dithering and no dithering.
It shows that dithering increases the size of the file.
It presents that dithering should only be chosen for this image, if the quality of the compressed image is unacceptable on its own .


Image 2   

original image          

original image png

                                                   JPEG FORMAT

                                                                    best value
The difference between the image at 60% and the image at 100% is not an issue, they are almost identical. In regards to the purpose of image compression, there is not a point choosing this image at 100% over the image at 60%, as the increase in file size (266 KB) becomes redundant when concerned with image compression.

Image 2-jpeg(60%)

image 2-jpeg(100%)
The main reason for the little difference between these two images is that the image uses mainly primary colours. Therefore reducing the amount of image pixels has little impact as it is using very few colours.

                                                                      Lowest acceptable Quality

The lowest quality that is acceptable is the 30%-medium quality. After that it starts to get very grainy, being able to see the image breaking up into boxes.

                                                     image 2 -JPEG (30%)

This graph again shows that there is big increase with both the quality of the image and the size of the file. There is a big difference between the image at 80% and 100%.Emphasing the redundancy in choosing the image at maximum quality.


                                                           GIF format

                                                           best value
The Image below provides the best value for this image with 128 colours in the palette and no dithering. This is good quality in regards to the size of the file,196KB.Whearas, the image with all its palette colours without dither is 242KB and the image with 256 of its palettes and has dithering is 251 KB.

                                                                       Image 2 GIF(128) no dither

                                       Lowest acceptable Quality                              

The lowest acceptable number of colours is 64 with dithering. This mainly to do with the wall in the background becomes too blurry or unrecognisable from original image if dithering is not picked with 64 palette colours.

                                                           Image 2 GIF(64) dither

                                            These two graphs compare dithering and no dithering. It shows again that dither increases the size of the file.


                                       Image 3

                                              original image

                                                                  original image png


          JPEG Format

 This graph again shows that as the image quality increases so does the size of this file.
best value
 The Image providing the best value for this image is 60% of its palettes. The size of this image is 98KB.This is very low when considering that that the size of this file at 100% is 308KB.
image 3 JPG(60%) 
Lowest acceptable Quality
Lowest acceptable quality for
 this image is 30% of the colours.There are too many colours and shades of colours for this image resolution to be any smaller.
image 3 JPG(30%)  

GIF Format

best value
The Image below providing the best value is the image with 128 colours without dithering, it occupies 174 KB compared to the image at maximum without dithering is 205KB and the image with maximum quality with dithering occupies 222KB
 image 3 GIF(128)-no dither 

Lowest acceptable Quality
The lowest acceptable number of colours in a palette for this image is 64 colours with dithering. Other values lower than this started blur,especially the writing on the wall and the windows

 image 3 GIF(64)-no dither
   These two graphs compare dithering and no dithering. 



 Guidelines for web developers

In regards to web developers the guidelines for image compression is very simple. It is very important when using software like Photoshop to save all images at different resolutions. The first thing is to save images for the web. When saving images in JPG format you should save five types of image quality. Such as low, medium, high, very high and maximum quality, in the GIF format you must save the files using both dithering and no dither. This will show you the two options available to you. With the GIF format the dither option is only good for lower quality images as it simulates colours not found in the palettes. This is a useful feature the image becomes unrecognisable, blurry and too dark because of the lack colours. In most cases, diffusion is not needed when picking the image with the best value. It will only increase the size of the file and sometimes takes away the sharpness of the image. Lastly, it is important to magnify the images to see when its crispness starts to diminish and always be aware of the file size.
In conclusion, as the quality of the image increases so does the size of the file, dramatically. Furthermore, it is clear from the graphs I have provided that dithering increase the size of the image. In one example was dithering the right choice in regards to best value for an image. Dithering is used mainly when choosing the lowest quality of image for the web. The main reason for the decrease in the quality of the images is a factor relating to the amount of colours in the palette. The only way to increase the quality of the image is to use dithering. This is why when choosing dithering you must choose quality over file size, as it is simulating colours not found in the palette.

Week 10

This week we looked at Google Analytics. We discussed how web servers keep logs of webpages that are requested. These logs include IP addresses and time of file requested. Talked about how Google Analytics are better than logs and anyone can use Google Analytics for a website or a blog. Google is able to gather more information about users than logs are able to collect. To use Google analytics you have to add a unique code to the pages you want to track. This code sends a request to the Google server. It offers information about the amount of visitors visiting the site, which web browser the site used to view the site, which country the users come from and the source of the traffic.

In the lab, we worked on finishing assignment two, which was due for noon the following day.

Sunday, 14 April 2013

Week 09

This week in our lectures, we discussed video compression and Podcasting. In regards to video compression we discussed how a digital video are just a sequence of frames. Such as P.A.L using 24 frames per second whereas cinema's using 25 frames per second. We learnt how important compression is as the average size (640*480*25fps*24bpp) a video stores is 21 Mbytes per second. We learned about two types of compression Intraframe and Interframe. Intraframe reduces the size of the frame within a single frame, whereas an interframe compresses the similarities between frames. Another form of compression, we looked at was block based motion which searches around for a block of data that can be copied and pasted between frames.

In our second lecture, we looked at podcast. We discussed how RSS feeds led to the creation of podcasts. Content can be accessed without constantly going to the site. The idea of adding enclosure audio or image files to an RSS feed led to the creation of podcasts, which can be downloaded automatically. This has developed in pre-recorded or edited radio programs being posted on the internet. It wasn't until Apple supported podcasting in 2005, that podcast became popular. Where a podcast could be downloaded and synched to your iPod automatically.

Monday, 25 March 2013

Week 08

This week, we looked at dithering, transparency, GIF, JPEG and PNG. We were shown examples of dithering and given examples of what colour was being simulated, by getting the average weight of RGB values. We were told about Graphics Interchange Format (GIF) and run length encoding of pixels, which needs long runs of the same colour to be successful.
We also talked about PNG- up to 32 bits per pixel, which was meant to be an alternative to GIF, however it was unsuccessful.
Also, we discussed JPEG and its two types of image compression such as lossy and lossless. Lossless compression is where the decompressed image is identical to the original image. Whereas, lossy is the opposite, the decompressed image isn't identical to the original. It was shown how the file size is directionally proportional to the image quality and at some point the cost of the file size is not worth the quality.
Lastly, we discussed transparency, how image formats such as GIF support transparency and how applications such as Photoshop use it to put parts of an image into another image. It also increases the file size of an image as it requires each pixel to have a value.

In the labs, our group definitely decided not to do the Google online advertising campaign. Instead we had to individually choose an essay title. I chose privacy vs. piracy. I feel this will be an essay topic to write about.

Sunday, 17 March 2013

Week 07

This week, we looked at pixel depth reduction and dithering. We first looked at image compression and the two types called Lossy and lossless. Lossless produces an exact replica of original image when compressed. Whereas Lossy compression doesn't produce an exact replica of original image but has higher compression ratio. We looked at the difference between compression ratio and quality of the image. It was shown on a graph how approximation of the original image being generated decrease as compression ratio increases. 
Another way to compress an image is sub-sampling, deleting every second row of pixels and every second column. Pixel depth reduction is an image compression method in the JPG format. The number of bits per pixel is reduced.
A colour Look UP Table (CLUT) also called a palette is used to map pixel values to colours. If you use a colour look up table, to re-code an image, dithering simulates colours not in the palette by choosing similar colours i.e. the weighted average of the RGB values of the colour.