#include "gstaudiometa.h"
+static gboolean
+gst_audio_downmix_meta_init (GstMeta * meta, gpointer params,
+ GstBuffer * buffer)
+{
+ GstAudioDownmixMeta *dmeta = (GstAudioDownmixMeta *) meta;
+
+ dmeta->from_position = dmeta->to_position = NULL;
+ dmeta->from_channels = dmeta->to_channels = 0;
+ dmeta->matrix = NULL;
+
+ return TRUE;
+}
+
+static void
+gst_audio_downmix_meta_free (GstMeta * meta, GstBuffer * buffer)
+{
+ GstAudioDownmixMeta *dmeta = (GstAudioDownmixMeta *) meta;
+
+ g_free (dmeta->from_position);
+ if (dmeta->matrix) {
+ g_free (*dmeta->matrix);
+ g_free (dmeta->matrix);
+ }
+}
+
static void
gst_audio_downmix_meta_copy (GstBuffer * dest, GstMeta * meta,
GstBuffer * buffer, gsize offset, gsize size)
{
- GstAudioDownmixMeta *dmeta, *smeta;
+ GstAudioDownmixMeta *smeta;
smeta = (GstAudioDownmixMeta *) meta;
- dmeta = gst_buffer_add_audio_downmix_meta (dest);
+ gst_buffer_add_audio_downmix_meta (dest, smeta->from_position,
+ smeta->from_channels, smeta->to_position, smeta->to_channels,
+ (const gfloat **) smeta->matrix);
+}
+
+/**
+ * gst_buffer_get_audio_downmix_meta_for_channels:
+ * @buffer: a #GstBuffer
+ * @to_position: the channel positions of the destination
+ * @to_channels: The number of channels of the destination
+ * @matrix: The matrix coefficients.
+ *
+ * Find the #GstAudioDownmixMeta on @buffer for the given destination
+ * channel positions.
+ *
+ * Returns: the #GstAudioDownmixMeta on @buffer.
+ */
+GstAudioDownmixMeta *
+gst_buffer_get_audio_downmix_meta_for_channels (GstBuffer * buffer,
+ const GstAudioChannelPosition * to_position, gint to_channels)
+{
+ gpointer state = NULL;
+ GstMeta *meta;
+ const GstMetaInfo *info = GST_AUDIO_DOWNMIX_META_INFO;
+
+ while ((meta = gst_buffer_iterate_meta (buffer, &state))) {
+ if (meta->info->api == info->api) {
+ GstAudioDownmixMeta *ameta = (GstAudioDownmixMeta *) meta;
+ if (ameta->to_channels == to_channels &&
+ memcmp (ameta->to_position, to_position,
+ sizeof (GstAudioChannelPosition) * to_channels) == 0)
+ return ameta;
+ }
+ }
+ return NULL;
+}
+
+/**
+ * gst_buffer_add_audio_downmix_meta:
+ * @buffer: a #GstBuffer
+ * @from_position: the channel positions of the source
+ * @from_channels: The number of channels of the source
+ * @to_position: the channel positions of the destination
+ * @to_channels: The number of channels of the destination
+ * @matrix: The matrix coefficients.
+ *
+ * Attaches GstAudioDownmixMeta metadata to @buffer with the given parameters.
+ *
+ * @matrix is an two-dimensional array of @to_channels times @from_channels
+ * coefficients, i.e. the i-th output channels is constructed by multiplicating
+ * the input channels with the coefficients in @matrix[i] and taking the sum
+ * of the results.
+ *
+ * Returns: the #GstAudioDownmixMeta on @buffer.
+ */
+GstAudioDownmixMeta *
+gst_buffer_add_audio_downmix_meta (GstBuffer * buffer,
+ const GstAudioChannelPosition * from_position, gint from_channels,
+ const GstAudioChannelPosition * to_position, gint to_channels,
+ const gfloat ** matrix)
+{
+ GstAudioDownmixMeta *meta;
+ gint i;
+
+ g_return_val_if_fail (from_position != NULL, NULL);
+ g_return_val_if_fail (from_channels > 0, NULL);
+ g_return_val_if_fail (to_position != NULL, NULL);
+ g_return_val_if_fail (to_channels > 0, NULL);
+ g_return_val_if_fail (matrix != NULL, NULL);
+
+ meta =
+ (GstAudioDownmixMeta *) gst_buffer_add_meta (buffer,
+ GST_AUDIO_DOWNMIX_META_INFO, NULL);
+
+ meta->from_channels = from_channels;
+ meta->to_channels = to_channels;
+
+ meta->from_position =
+ g_new (GstAudioChannelPosition, meta->from_channels + meta->to_channels);
+ meta->to_position = meta->from_position + meta->from_channels;
+ memcpy (meta->from_position, from_position,
+ sizeof (GstAudioChannelPosition) * meta->from_channels);
+ memcpy (meta->to_position, to_position,
+ sizeof (GstAudioChannelPosition) * meta->to_channels);
+
+ meta->matrix = g_new (gfloat *, meta->to_channels);
+ meta->matrix[0] = g_new (gfloat, meta->from_channels * meta->to_channels);
+ memcpy (meta->matrix[0], matrix[0], sizeof (gfloat) * meta->from_channels);
+ for (i = 1; i < meta->to_channels; i++) {
+ meta->matrix[i] = meta->matrix[0] + i * meta->from_channels;
+ memcpy (meta->matrix[i], matrix[i], sizeof (gfloat) * meta->from_channels);
+ }
- memcpy (dmeta, smeta, sizeof (GstAudioDownmixMeta));
+ return meta;
}
const GstMetaInfo *
if (audio_downmix_meta_info == NULL) {
audio_downmix_meta_info =
gst_meta_register (GST_AUDIO_DOWNMIX_META_API, "GstAudioDownmixMeta",
- sizeof (GstAudioDownmixMeta), (GstMetaInitFunction) NULL,
- (GstMetaFreeFunction) NULL, gst_audio_downmix_meta_copy,
- (GstMetaTransformFunction) NULL);
+ sizeof (GstAudioDownmixMeta),
+ (GstMetaInitFunction) gst_audio_downmix_meta_init,
+ (GstMetaFreeFunction) gst_audio_downmix_meta_free,
+ gst_audio_downmix_meta_copy, (GstMetaTransformFunction) NULL);
}
return audio_downmix_meta_info;
}
/**
* GstAudioDownmixMeta:
* @meta: parent #GstMeta
- * @channels: the number of channels of the destination
+ * @from_position: the channel positions of the source
+ * @to_position: the channel positions of the destination
+ * @from_channels: the number of channels of the source
+ * @to_channels: the number of channels of the destination
* @matrix: the matrix coefficients.
*
* Extra buffer metadata describing audio downmixing matrix. This metadata is
* attached to audio buffers and contains a matrix to downmix the buffer number
* of channels to @channels.
+ *
+ * @matrix is an two-dimensional array of @to_channels times @from_channels
+ * coefficients, i.e. the i-th output channels is constructed by multiplicating
+ * the input channels with the coefficients in @matrix[i] and taking the sum
+ * of the results.
*/
struct _GstAudioDownmixMeta {
GstMeta meta;
- guint channels;
- gfloat matrix[64];
+ GstAudioChannelPosition *from_position;
+ GstAudioChannelPosition *to_position;
+ gint from_channels, to_channels;
+ gfloat **matrix;
};
const GstMetaInfo * gst_audio_downmix_meta_get_info (void);
#define gst_buffer_get_audio_downmix_meta(b) ((GstAudioDownmixMeta*)gst_buffer_get_meta((b),GST_AUDIO_DOWNMIX_META_INFO))
-#define gst_buffer_add_audio_downmix_meta(b) ((GstAudioDownmixMeta*)gst_buffer_add_meta((b),GST_AUDIO_DOWNMIX_META_INFO, NULL))
+GstAudioDownmixMeta * gst_buffer_get_audio_downmix_meta_for_channels (GstBuffer *buffer,
+ const GstAudioChannelPosition *to_position,
+ gint to_channels);
+
+GstAudioDownmixMeta * gst_buffer_add_audio_downmix_meta (GstBuffer *buffer,
+ const GstAudioChannelPosition *from_position,
+ gint from_channels,
+ const GstAudioChannelPosition *to_position,
+ gint to_channels,
+ const gfloat **matrix);
G_END_DECLS