So it turns out that pinyin can't be reversed back to Chinese characters. However, I keep seeing images like the ones below for different languages (the images below are for Hindi and Japanese, but there are others). Basically they show (in some cases) abugidas (consonant/vowel pairs), or just consonants/vowels separately like the Latin alphabet. So these are sound-based scripts, as opposed to Chinese which is image based. That makes sense then why pinyin wouldn't directly map.
But I'm basically wondering if there is a 1-to-1 mapping, then, between the romanized spelling of say a Japanese or Hindi word, vs. the spelling in the native script.
I'm asking because it seems that English isn't actually a sound-based language. Or more specifically, it is only partially sound-based. You can have two words sound the same, like
brake (1 primary meaning) and
break (2 primary meanings, break something, and take a break). So you have 1 phonological spelling with IPA that maps to 2 different English orthographic spellings, and a bunch of different meanings. This creates a problem similar to Pinyin, in that you have to disambiguate which spelling you are considering. Chinese has almost 100 meanings for /yi4/. You also have patterns like
worse which are the same orthographically but different phonologically.
I'm wondering if these other languages have this same problem. That is, if languages like Hindi, Japanese, even Inuktitut, or other languages that have their own script, yet are sound-based. That is, the pronunciation of the word can map to multiple symbols in that language. Or perhaps that's a benefit of these languages, that they have a direct 1-to-1 mapping between the romanized pronunciation and the native script.
The languages I'm particularly interested in are any with custom scripts (Sanskrit/Hindi, Japanese, Tamil, Inuktitut, Amharic, etc.), or even those with Latin script (Swahili, Malaysian, etc.).