* decoder to draw a horizontal band. It improves cache usage. Not
* all codecs can do that. You must check the codec capabilities
* beforehand.
- * The functino is also used by hardware acceleration APIs as a callback
- * to pass specific (partially decoded) data to the calling application
- * so that the data can be passed to the rendering hardware.
- * In that mode all relevant function parameters are inside a special
- * structure passed by AVFrame in place of the pixel data.
- * The exact structure depends on the acceleration API.
- * The application is allowed to make changes in the structure.
+ * The function is also used by hardware acceleration APIs.
+ * It is called at least once during frame decoding to pass
+ * the data needed for hardware render.
+ * In that mode instead of pixel data, AVFrame points to
+ * a structure specific to the acceleration API. The application
+ * reads the structure and can change some fields to indicate progress
+ * or mark state.
* - encoding: unused
* - decoding: Set by user.
* @param height the height of the slice