From ff7f3216fe76e0a4598bdf737671a5e25a780ded Mon Sep 17 00:00:00 2001 From: Matthias Vogelgesang Date: Wed, 20 Mar 2013 10:03:52 +0100 Subject: uca_camera_grab takes a gpointer and returns bool --- docs/manual.md | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) (limited to 'docs/manual.md') diff --git a/docs/manual.md b/docs/manual.md index 0dd9c66..0b81bdb 100644 --- a/docs/manual.md +++ b/docs/manual.md @@ -185,22 +185,18 @@ To synchronously grab frames, first start the camera: g_assert_no_error (error); ~~~ -Now you have two options with regard to memory buffers. If you already have a -suitable sized buffer, just pass it to `uca_camera_grab`. Otherwise pass a -pointer pointing to `NULL` (this is different from a `NULL` pointer!). In this -case memory will be allocated for you: +Now, you have to allocate a suitably sized buffer and pass it to +`uca_camera_grab`. ~~~ {.c} - gpointer buffer_1 = NULL; /* A pointer pointing to NULL */ - gpointer buffer_2 = g_malloc0 (640 * 480 * 2); + gpointer buffer = g_malloc0 (640 * 480 * 2); - /* Memory will be allocated. Remember to free it! */ - uca_camera_grab (camera, &buffer_1, &error); - - /* Memory buffer will be used */ - uca_camera_grab (camera, &buffer_2, &error); + uca_camera_grab (camera, buffer, &error); ~~~ +You have to make sure that the buffer is large enough by querying the size of +the region of interest and the number of bits that are transferred. + ### Getting and setting camera parameters -- cgit v1.2.3