The Phimpme Android application comes with a well-featured camera to take high resolution photographs. It features an auto mode in the camera as well as a manual mode for users who likes to customise the camera experience according to their own liking. It provides the users to select from the range of ISO values supported by their devices with a manual mode to enhance the images in case the auto mode fails on certain circumstances such as low lighting conditions.

In this tutorial, I will be discussing how we achieved this in Phimpme Android with some code snippets and screenshots.

To provide the users with an option to select from the range of ISO values, the first thing we need to do is scan the phone for all the supported values of ISO and store it in an arraylist to be used to display later on. This can be done by the snippet provided below:

String iso_values = parameters.get("iso-values");
if( iso_values == null ) {
 iso_values = parameters.get("iso-mode-values"); // Galaxy Nexus
 if( iso_values == null ) {
    iso_values = parameters.get("iso-speed-values"); // Micromax A101
    if( iso_values == null )
       iso_values = parameters.get("nv-picture-iso-values"); // LG dual P990

Every device supports a different set of keyword to provide the list of ISO values. Hence, we have tried to add every possible keywords to extract the values. Some of the keywords used above covers almost 90% of the android devices and gets the set of ISO values successfully.

For the devices which supports the ISO values but doesn’t provide the keyword to extract the ISO values, we can provide the standard list of ISO values manually using the code snippet provided below:

values.add("200");
values.add("400");
values.add("800");
values.add("1600");

After extracting the set of ISO values, we need to create a list to display to the user and upon selection of the particular ISO value as depicted in the Phimpme camera screenshot below

Now to set the selected ISO value, we first need to get the ISO key to set the ISO values as depicted in the code snippet provided below:

if( parameters.get(iso_key) == null ) {
 iso_key = "iso-speed"; // Micromax A101
 if( parameters.get(iso_key) == null ) {
    iso_key = "nv-picture-iso"; // LG dual P990
    if( parameters.get(iso_key) == null ) {
       if ( Build.MODEL.contains("Z00") )
          iso_key = "iso"; // Asus Zenfone 2 Z00A and Z008

Getting the key to set the ISO values is similar to getting the key to extract the ISO values from the device. The above listed ISO keys to set the values covers most of the devices.

Now after we have got the ISO key, we need to change the camera parameter to reflect the selected change.

parameters.set(iso_key, supported_values.selected_value);
setCameraParameters(parameters);

To get the full source code on how to set the ISO values manually, please refer to the Phimpme Android repository.

Resources

1. Stackoverflow – Keywords to extract ISO values from the device: http://stackoverflow.com/questions/2978095/android-camera-api-iso-setting
2. Open camera Android source code: https://sourceforge.net/p/opencamera/code/ci/master/tree/
3. Blog – Learn more about ISO values in photography: https://photographylife.com/what-is-iso-in-photography