AVFrame: add side data.

libavutil/frame.c

@@ -20,6 +20,7 @@
 #include "audioconvert.h"
 #include "buffer.h"
 #include "common.h"
+#include "dict.h"
 #include "frame.h"
 #include "imgutils.h"
 #include "mem.h"
@@ -273,6 +274,13 @@ void av_frame_unref(AVFrame *frame)
 {
     int i;
 
+    for (i = 0; i < frame->nb_side_data; i++) {
+        av_freep(&frame->side_data[i]->data);
+        av_dict_free(&frame->side_data[i]->metadata);
+        av_freep(&frame->side_data[i]);
+    }
+    av_freep(&frame->side_data);
+
     for (i = 0; i < FF_ARRAY_ELEMS(frame->buf); i++)
         av_buffer_unref(&frame->buf[i]);
     for (i = 0; i < frame->nb_extended_buf; i++)
@@ -353,6 +361,8 @@ int av_frame_make_writable(AVFrame *frame)
 
 int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
 {
+    int i;
+
     dst->key_frame           = src->key_frame;
     dst->pict_type           = src->pict_type;
     dst->sample_aspect_ratio = src->sample_aspect_ratio;
@@ -367,6 +377,23 @@ int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
     dst->coded_picture_number = src->coded_picture_number;
     dst->display_picture_number = src->display_picture_number;
 
+    for (i = 0; i < src->nb_side_data; i++) {
+        const AVFrameSideData *sd_src = src->side_data[i];
+        AVFrameSideData *sd_dst = av_frame_new_side_data(dst, sd_src->type,
+                                                         sd_src->size);
+        if (!sd_dst) {
+            for (i = 0; i < dst->nb_side_data; i++) {
+                av_freep(&dst->side_data[i]->data);
+                av_freep(&dst->side_data[i]);
+                av_dict_free(&dst->side_data[i]->metadata);
+            }
+            av_freep(&dst->side_data);
+            return AVERROR(ENOMEM);
+        }
+        memcpy(sd_dst->data, sd_src->data, sd_src->size);
+        av_dict_copy(&sd_dst->metadata, sd_src->metadata, 0);
+    }
+
     return 0;
 }
 
@@ -399,3 +426,48 @@ AVBufferRef *av_frame_get_plane_buffer(AVFrame *frame, int plane)
     }
     return NULL;
 }
+
+AVFrameSideData *av_frame_new_side_data(AVFrame *frame,
+                                        enum AVFrameSideDataType type,
+                                        int size)
+{
+    AVFrameSideData *ret, **tmp;
+
+    if (frame->nb_side_data > INT_MAX / sizeof(*frame->side_data) - 1)
+        return NULL;
+
+    tmp = av_realloc(frame->side_data,
+                     (frame->nb_side_data + 1) * sizeof(*frame->side_data));
+    if (!tmp)
+        return NULL;
+    frame->side_data = tmp;
+
+    ret = av_mallocz(sizeof(*ret));
+    if (!ret)
+        return NULL;
+
+    ret->data = av_malloc(size);
+    if (!ret->data) {
+        av_freep(&ret);
+        return NULL;
+    }
+
+    ret->size = size;
+    ret->type = type;
+
+    frame->side_data[frame->nb_side_data++] = ret;
+
+    return ret;
+}
+
+AVFrameSideData *av_frame_get_side_data(AVFrame *frame,
+                                        enum AVFrameSideDataType type)
+{
+    int i;
+
+    for (i = 0; i < frame->nb_side_data; i++) {
+        if (frame->side_data[i]->type == type)
+            return frame->side_data[i];
+    }
+    return NULL;
+}

libavutil/frame.h

@@ -26,9 +26,23 @@
 
 #include "avutil.h"
 #include "buffer.h"
+#include "dict.h"
 #include "rational.h"
 #include "samplefmt.h"
 
+enum AVFrameSideDataType {
+    /**
+     * The data is the AVPanScan struct defined in libavcodec.
+     */
+    AV_FRAME_DATA_PANSCAN,
+};
+
+typedef struct AVFrameSideData {
+    enum AVFrameSideDataType type;
+    uint8_t *data;
+    int      size;
+    AVDictionary *metadata;
+} AVFrameSideData;
 
 /**
  * This structure describes decoded (raw) audio or video data.
@@ -306,6 +320,9 @@ typedef struct AVFrame {
      * Number of elements in extended_buf.
      */
     int        nb_extended_buf;
+
+    AVFrameSideData **side_data;
+    int            nb_side_data;
 } AVFrame;
 
 /**
@@ -413,6 +430,7 @@ int av_frame_make_writable(AVFrame *frame);
  * Metadata for the purpose of this function are those fields that do not affect
  * the data layout in the buffers.  E.g. pts, sample rate (for audio) or sample
  * aspect ratio (for video), but not width/height or channel layout.
+ * Side data is also copied.
  */
 int av_frame_copy_props(AVFrame *dst, const AVFrame *src);
 
@@ -426,4 +444,24 @@ int av_frame_copy_props(AVFrame *dst, const AVFrame *src);
  */
 AVBufferRef *av_frame_get_plane_buffer(AVFrame *frame, int plane);
 
+/**
+ * Add a new side data to a frame.
+ *
+ * @param frame a frame to which the side data should be added
+ * @param type type of the added side data
+ * @param size size of the side data
+ *
+ * @return newly added side data on success, NULL on error
+ */
+AVFrameSideData *av_frame_new_side_data(AVFrame *frame,
+                                        enum AVFrameSideDataType type,
+                                        int size);
+
+/**
+ * @return a pointer to the side data of a given type on success, NULL if there
+ * is no side data with such type in this frame.
+ */
+AVFrameSideData *av_frame_get_side_data(AVFrame *frame,
+                                        enum AVFrameSideDataType type);
+
 #endif /* AVUTIL_FRAME_H */