lavu/imgutils: create misc functions for dealing with buffers

Move the lavc/imgconvert functions and rename them as follows:
avpicture_get_size -> av_image_get_buffer_size()
avpicture_fill     -> av_image_fill_arrays()
avpicture_layout   -> av_image_copy_to_buffer()

The new functions have an align parameter, which allows to define the
linesize alignment assumed in the buffer (which is set or read).

The names of the functions are consistent with the lavu/samples API
(av_samples_get_buffer_size(), av_samples_fill_arrays()).

1 files changed, 10 insertions, 38 deletions

diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index d9da2ad2e1..21a0ed90eb 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -4261,42 +4261,19 @@ int avpicture_alloc(AVPicture *picture, enum PixelFormat pix_fmt, int width, int
 void avpicture_free(AVPicture *picture);
 
 /**
- * Fill in the AVPicture fields.
- * The fields of the given AVPicture are filled in by using the 'ptr' address
- * which points to the image data buffer. Depending on the specified picture
- * format, one or multiple image data pointers and line sizes will be set.
- * If a planar format is specified, several pointers will be set pointing to
- * the different picture planes and the line sizes of the different planes
- * will be stored in the lines_sizes array.
- * Call with ptr == NULL to get the required size for the ptr buffer.
- *
- * To allocate the buffer and fill in the AVPicture fields in one call,
- * use avpicture_alloc().
- *
- * @param picture AVPicture whose fields are to be filled in
- * @param ptr Buffer which will contain or contains the actual image data
- * @param pix_fmt The format in which the picture data is stored.
- * @param width the width of the image in pixels
- * @param height the height of the image in pixels
- * @return size of the image data in bytes
+ * Fill in the AVPicture fields, always assume a linesize alignment of
+ * 1.
+ *
+ * @see av_image_fill_arrays()
  */
 int avpicture_fill(AVPicture *picture, uint8_t *ptr,
                    enum PixelFormat pix_fmt, int width, int height);
 
 /**
- * Copy pixel data from an AVPicture into a buffer.
- * The data is stored compactly, without any gaps for alignment or padding
- * which may be applied by avpicture_fill().
- *
- * @see avpicture_get_size()
+ * Copy pixel data from an AVPicture into a buffer, always assume a
+ * linesize alignment of 1.
  *
- * @param[in] src AVPicture containing image data
- * @param[in] pix_fmt The format in which the picture data is stored.
- * @param[in] width the width of the image in pixels.
- * @param[in] height the height of the image in pixels.
- * @param[out] dest A buffer into which picture data will be copied.
- * @param[in] dest_size The size of 'dest'.
- * @return The number of bytes written to dest, or a negative value (error code) on error.
+ * @see av_image_copy_to_buffer()
  */
 int avpicture_layout(const AVPicture* src, enum PixelFormat pix_fmt, int width, int height,
                      unsigned char *dest, int dest_size);
@@ -4304,14 +4281,9 @@ int avpicture_layout(const AVPicture* src, enum PixelFormat pix_fmt, int width,
 /**
  * Calculate the size in bytes that a picture of the given width and height
  * would occupy if stored in the given picture format.
- * Note that this returns the size of a compact representation as generated
- * by avpicture_layout(), which can be smaller than the size required for e.g.
- * avpicture_fill().
- *
- * @param pix_fmt the given picture format
- * @param width the width of the image
- * @param height the height of the image
- * @return Image data size in bytes or -1 on error (e.g. too large dimensions).
+ * Always assume a linesize alignment of 1.
+ *
+ * @see av_image_get_buffer_size().
  */
 int avpicture_get_size(enum PixelFormat pix_fmt, int width, int height);