@@ -13,6 +13,10 @@ libavutil:   2011-04-18

 API changes, most recent first:

+2011-xx-xx - xxxxxxx - lavu 51.18.0

+  Add av_samples_get_buffer_size(), av_samples_fill_arrays(), and

+  av_samples_alloc(), to samplefmt.h.

+

 2011-xx-xx - xxxxxxx - lavu 51.17.0

   Add planar sample formats and av_sample_fmt_is_planar() to samplefmt.h.

@@ -153,7 +153,7 @@

  */

 #define LIBAVUTIL_VERSION_MAJOR 51

-#define LIBAVUTIL_VERSION_MINOR 17

+#define LIBAVUTIL_VERSION_MINOR 18

 #define LIBAVUTIL_VERSION_MICRO  0

 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \

@@ -92,3 +92,68 @@ int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt)

          return 0;

      return sample_fmt_info[sample_fmt].planar;

 }

+

+int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples,

+                               enum AVSampleFormat sample_fmt, int align)

+{

+    int line_size;

+    int sample_size = av_get_bytes_per_sample(sample_fmt);

+    int planar      = av_sample_fmt_is_planar(sample_fmt);

+

+    /* validate parameter ranges */

+    if (!sample_size || nb_samples <= 0 || nb_channels <= 0)

+        return AVERROR(EINVAL);

+

+    /* check for integer overflow */

+    if (nb_channels > INT_MAX / align ||

+        (int64_t)nb_channels * nb_samples > (INT_MAX - (align * nb_channels)) / sample_size)

+        return AVERROR(EINVAL);

+

+    line_size = planar ? FFALIGN(nb_samples * sample_size,               align) :

+                         FFALIGN(nb_samples * sample_size * nb_channels, align);

+    if (linesize)

+        *linesize = line_size;

+

+    return planar ? line_size * nb_channels : line_size;

+}

+

+int av_samples_fill_arrays(uint8_t **audio_data, int *linesize,

+                           uint8_t *buf, int nb_channels, int nb_samples,

+                           enum AVSampleFormat sample_fmt, int align)

+{

+    int ch, planar, buf_size;

+

+    planar   = av_sample_fmt_is_planar(sample_fmt);

+    buf_size = av_samples_get_buffer_size(linesize, nb_channels, nb_samples,

+                                          sample_fmt, align);

+    if (buf_size < 0)

+        return buf_size;

+

+    audio_data[0] = buf;

+    for (ch = 1; planar && ch < nb_channels; ch++)

+        audio_data[ch] = audio_data[ch-1] + *linesize;

+

+    return 0;

+}

+

+int av_samples_alloc(uint8_t **audio_data, int *linesize, int nb_channels,

+                     int nb_samples, enum AVSampleFormat sample_fmt, int align)

+{

+    uint8_t *buf;

+    int size = av_samples_get_buffer_size(NULL, nb_channels, nb_samples,

+                                          sample_fmt, align);

+    if (size < 0)

+        return size;

+

+    buf = av_mallocz(size);

+    if (!buf)

+        return AVERROR(ENOMEM);

+

+    size = av_samples_fill_arrays(audio_data, linesize, buf, nb_channels,

+                                  nb_samples, sample_fmt, align);

+    if (size < 0) {

+        av_free(buf);

+        return size;

+    }

+    return 0;

+}

@@ -92,4 +92,57 @@ int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt);

  */

 int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt);

+/**

+ * Get the required buffer size for the given audio parameters.

+ *

+ * @param[out] linesize calculated linesize, may be NULL

+ * @param nb_channels   the number of channels

+ * @param nb_samples    the number of samples in a single channel

+ * @param sample_fmt    the sample format

+ * @return              required buffer size, or negative error code on failure

+ */

+int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples,

+                               enum AVSampleFormat sample_fmt, int align);

+

+/**

+ * Fill channel data pointers and linesize for samples with sample

+ * format sample_fmt.

+ *

+ * The pointers array is filled with the pointers to the samples data:

+ * for planar, set the start point of each channel's data within the buffer,

+ * for packed, set the start point of the entire buffer only.

+ *

+ * The linesize array is filled with the aligned size of each channel's data

+ * buffer for planar layout, or the aligned size of the buffer for all channels

+ * for packed layout.

+ *

+ * @param[out] audio_data  array to be filled with the pointer for each channel

+ * @param[out] linesize    calculated linesize

+ * @param buf              the pointer to a buffer containing the samples

+ * @param nb_channels      the number of channels

+ * @param nb_samples       the number of samples in a single channel

+ * @param sample_fmt       the sample format

+ * @param align            buffer size alignment (1 = no alignment required)

+ * @return                 0 on success or a negative error code on failure

+ */

+int av_samples_fill_arrays(uint8_t **audio_data, int *linesize, uint8_t *buf,

+                           int nb_channels, int nb_samples,

+                           enum AVSampleFormat sample_fmt, int align);

+

+/**

+ * Allocate a samples buffer for nb_samples samples, and fill data pointers and

+ * linesize accordingly.

+ * The allocated samples buffer can be freed by using av_freep(&audio_data[0])

+ *

+ * @param[out] audio_data  array to be filled with the pointer for each channel

+ * @param[out] linesize    aligned size for audio buffer(s)

+ * @param nb_channels      number of audio channels

+ * @param nb_samples       number of samples per channel

+ * @param align            buffer size alignment (1 = no alignment required)

+ * @return                 0 on success or a negative error code on failure

+ * @see av_samples_fill_arrays()

+ */

+int av_samples_alloc(uint8_t **audio_data, int *linesize, int nb_channels,

+                     int nb_samples, enum AVSampleFormat sample_fmt, int align);

+

 #endif /* AVUTIL_SAMPLEFMT_H */