Drop-in python script to linearly tween numeric values in processing profiles across a set of arbitrarily many RAW images

tween_pp3s.py

#!/usr/bin/python

import string, os

START_FILE_PATH = "start.pp3"
END_FILE_PATH   = "end.pp3"
RAW_FILES_DIR   = "raw"

# Load the contents of the start and end PP3 files (equal line numbers enforced!)

with open(START_FILE_PATH, "r") as start_file:
    start_lines = string.split(start_file.read(), "\n")

with open(END_FILE_PATH, "r") as end_file:
    end_lines = string.split(end_file.read(), "\n")

if len(start_lines) != len(end_lines):
    print "Sorry, I only work on start/end PP3s with the same number of lines!"
    exit
    
# Create an ordered list of all CR2 files in the raw directory

raw_files = []
for f in os.listdir(RAW_FILES_DIR):
    if os.path.isfile(os.path.join(RAW_FILES_DIR, f)) and f.endswith("CR2"):
        raw_files.append(f)
raw_files.sort()

if len(raw_files) < 2:
    print "At least two RAW files required, " + str(len(raw_files)) + " found!"
    exit

# Parse the values in the start and end PP3s to build a data structure
# representing both extremes at once. Each section is preserved separately
# as parameters may appear under the same name in different sections.
# All values are represented as strings unless they are tweenable, and then
# they will be tuple of exactly two ints or two floats.

params = {}

def int_or_float(val):
    try:
        return int(val)
    except ValueError:
        return float(val)

section = None
for line in start_lines:
    if line.startswith("["):
        section = line.replace("[","").replace("]","")
        params[section] = {}
        continue
    if "=" not in line:
        continue
    param, raw_value = string.split(line, "=", 2)
    try:
        num_value = int_or_float(raw_value)
    except ValueError:
        params[section][param] = raw_value
        continue
    params[section][param] = (num_value, None)

print "Tweens:"
section = None
for line in end_lines:
    if line.startswith("["):
        section = line.replace("[","").replace("]","")
        continue
    if "=" not in line:
        continue
    param, raw_value = string.split(line, "=", 2)
    try:
        num_value = int_or_float(raw_value)
    except ValueError:
        continue;
    if (type(params[section][param][0]) is type(num_value) and params[section][param][0] != num_value):
        params[section][param] = (params[section][param][0], num_value)
        print " * [" + section + "] " + param + ": " + str(params[section][param]) + " <" + ("int" if type(num_value) is int else "float") + ">"
    else:
        params[section][param] = raw_value

# Walk the raw file list generating a new PP3 file for each one
# Linearly tween all tweenable values

for idx, raw_file in enumerate(raw_files):
    percentage = float(idx) / float(len(raw_files) - 1)
    tweened_pp3 = ""
    for section in params:
        if (len(tweened_pp3) > 0):
            tweened_pp3 += "\n"
        tweened_pp3 += "[" + section + "]\n"
        for param in params[section]:
            pp3_val = params[section][param]
            if type(params[section][param]) is tuple:
                start, end = params[section][param]
                if type(start) is int:
                    pp3_val = str(start + int((end - start) * percentage))
                else:
                    pp3_val = str(start + (end - start) * percentage)
            tweened_pp3 += param + "=" + pp3_val + "\n"
    pp3_file = open(os.path.join(RAW_FILES_DIR, raw_file + ".pp3"), "w")
    pp3_file.write(tweened_pp3)
    pp3_file.close()
    print raw_file + ".pp3"

print "DONE.\nGenerated " + str(len(raw_files)) + " tweened PP3 files."