From 8e8a638a5f2a4eb58de0e017cce5a990baadd52c Mon Sep 17 00:00:00 2001 From: Claudio Felber Date: Tue, 22 Sep 2020 12:22:06 +0200 Subject: [PATCH] Update README.md with how to use quirc_flip() --- .gitignore | 1 + README.md | 17 +++++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/.gitignore b/.gitignore index a7494bc..54855db 100644 --- a/.gitignore +++ b/.gitignore @@ -9,3 +9,4 @@ libquirc.so* .*.swp *~ .DS_Store +.idea \ No newline at end of file diff --git a/README.md b/README.md index d70c5c3..78051ad 100644 --- a/README.md +++ b/README.md @@ -174,6 +174,23 @@ for (i = 0; i < num_codes; i++) { `quirc_code` and `quirc_data` are flat structures which don't need to be initialized or freed after use. +In case you also need to support horizontally flipped QR-codes (mirrored +images according to ISO 18004:2015, pages 6 and 62), you can make a second +decode attempt with the flipped image data whenever you get an ECC failure: + +```C + err = quirc_decode(&code, &data); + if (err == QUIRC_ERROR_DATA_ECC) { + quirc_flip(&code); + err = quirc_decode(&code, &data); + } + + if (err) + printf("DECODE FAILED: %s\n", quirc_strerror(err)); + else + printf("Data: %s\n", data.payload); +``` + Copyright --------- Copyright (C) 2010-2012 Daniel Beer <>