Move AVFrame from lavc to lavu.

Add AVBuffer-based reference counting API to it.

3 files changed, 832 insertions, 0 deletions

diff --git a/libavutil/Makefile b/libavutil/Makefile
index ef29d5c4b5..582fc31951 100644
--- a/libavutil/Makefile
+++ b/libavutil/Makefile
@@ -20,6 +20,7 @@ HEADERS = adler32.h                                                     \
           eval.h                                                        \
           fifo.h                                                        \
           file.h                                                        \
+          frame.h                                                       \
           hmac.h                                                        \
           imgutils.h                                                    \
           intfloat.h                                                    \
@@ -70,6 +71,7 @@ OBJS = adler32.o                                                        \
        fifo.o                                                           \
        file.o                                                           \
        float_dsp.o                                                      \
+       frame.o                                                          \
        hmac.o                                                           \
        imgutils.o                                                       \
        intfloat_readwrite.o                                             \
diff --git a/libavutil/frame.c b/libavutil/frame.c
new file mode 100644
index 0000000000..e84052eda0
--- /dev/null
+++ b/libavutil/frame.c
@@ -0,0 +1,401 @@
+/*
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "audioconvert.h"
+#include "buffer.h"
+#include "common.h"
+#include "frame.h"
+#include "imgutils.h"
+#include "mem.h"
+#include "samplefmt.h"
+
+static void get_frame_defaults(AVFrame *frame)
+{
+    if (frame->extended_data != frame->data)
+        av_freep(&frame->extended_data);
+
+    memset(frame, 0, sizeof(*frame));
+
+    frame->pts                 = AV_NOPTS_VALUE;
+    frame->key_frame           = 1;
+    frame->sample_aspect_ratio = (AVRational){ 0, 1 };
+    frame->format              = -1; /* unknown */
+    frame->extended_data       = frame->data;
+}
+
+AVFrame *av_frame_alloc(void)
+{
+    AVFrame *frame = av_mallocz(sizeof(*frame));
+
+    if (!frame)
+        return NULL;
+
+    get_frame_defaults(frame);
+
+    return frame;
+}
+
+void av_frame_free(AVFrame **frame)
+{
+    if (!frame || !*frame)
+        return;
+
+    av_frame_unref(*frame);
+    av_freep(frame);
+}
+
+static int get_video_buffer(AVFrame *frame, int align)
+{
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
+    int ret, i;
+
+    if (!desc)
+        return AVERROR(EINVAL);
+
+    if ((ret = av_image_check_size(frame->width, frame->height, 0, NULL)) < 0)
+        return ret;
+
+    if (!frame->linesize[0]) {
+        ret = av_image_fill_linesizes(frame->linesize, frame->format,
+                                      frame->width);
+        if (ret < 0)
+            return ret;
+
+        for (i = 0; i < 4 && frame->linesize[i]; i++)
+            frame->linesize[i] = FFALIGN(frame->linesize[i], align);
+    }
+
+    for (i = 0; i < 4 && frame->linesize[i]; i++) {
+        int h = frame->height;
+        if (i == 1 || i == 2)
+            h = -((-h) >> desc->log2_chroma_h);
+
+        frame->buf[i] = av_buffer_alloc(frame->linesize[i] * h);
+        if (!frame->buf[i])
+            goto fail;
+
+        frame->data[i] = frame->buf[i]->data;
+    }
+    if (desc->flags & PIX_FMT_PAL || desc->flags & PIX_FMT_PSEUDOPAL) {
+        av_buffer_unref(&frame->buf[1]);
+        frame->buf[1] = av_buffer_alloc(1024);
+        if (!frame->buf[1])
+            goto fail;
+        frame->data[1] = frame->buf[1]->data;
+    }
+
+    frame->extended_data = frame->data;
+
+    return 0;
+fail:
+    av_frame_unref(frame);
+    return AVERROR(ENOMEM);
+}
+
+static int get_audio_buffer(AVFrame *frame, int align)
+{
+    int channels = av_get_channel_layout_nb_channels(frame->channel_layout);
+    int planar   = av_sample_fmt_is_planar(frame->format);
+    int planes   = planar ? channels : 1;
+    int ret, i;
+
+    if (!frame->linesize[0]) {
+        ret = av_samples_get_buffer_size(&frame->linesize[0], channels,
+                                         frame->nb_samples, frame->format,
+                                         align);
+        if (ret < 0)
+            return ret;
+    }
+
+    if (planes > AV_NUM_DATA_POINTERS) {
+        frame->extended_data = av_mallocz(planes *
+                                          sizeof(*frame->extended_data));
+        frame->extended_buf  = av_mallocz((planes - AV_NUM_DATA_POINTERS) *
+                                          sizeof(*frame->extended_buf));
+        if (!frame->extended_data || !frame->extended_buf) {
+            av_freep(&frame->extended_data);
+            av_freep(&frame->extended_buf);
+            return AVERROR(ENOMEM);
+        }
+        frame->nb_extended_buf = planes - AV_NUM_DATA_POINTERS;
+    } else
+        frame->extended_data = frame->data;
+
+    for (i = 0; i < FFMIN(planes, AV_NUM_DATA_POINTERS); i++) {
+        frame->buf[i] = av_buffer_alloc(frame->linesize[0]);
+        if (!frame->buf[i]) {
+            av_frame_unref(frame);
+            return AVERROR(ENOMEM);
+        }
+        frame->extended_data[i] = frame->data[i] = frame->buf[i]->data;
+    }
+    for (i = 0; i < planes - AV_NUM_DATA_POINTERS; i++) {
+        frame->extended_buf[i] = av_buffer_alloc(frame->linesize[0]);
+        if (!frame->extended_buf[i]) {
+            av_frame_unref(frame);
+            return AVERROR(ENOMEM);
+        }
+        frame->extended_data[i + AV_NUM_DATA_POINTERS] = frame->extended_buf[i]->data;
+    }
+    return 0;
+
+}
+
+int av_frame_get_buffer(AVFrame *frame, int align)
+{
+    if (frame->format < 0)
+        return AVERROR(EINVAL);
+
+    if (frame->width > 0 && frame->height > 0)
+        return get_video_buffer(frame, align);
+    else if (frame->nb_samples > 0 && frame->channel_layout)
+        return get_audio_buffer(frame, align);
+
+    return AVERROR(EINVAL);
+}
+
+int av_frame_ref(AVFrame *dst, AVFrame *src)
+{
+    int i, ret = 0;
+
+    dst->format         = src->format;
+    dst->width          = src->width;
+    dst->height         = src->height;
+    dst->channel_layout = src->channel_layout;
+    dst->nb_samples     = src->nb_samples;
+
+    ret = av_frame_copy_props(dst, src);
+    if (ret < 0)
+        return ret;
+
+    /* duplicate the frame data if it's not refcounted */
+    if (!src->buf[0]) {
+        ret = av_frame_get_buffer(dst, 32);
+        if (ret < 0)
+            return ret;
+
+        if (src->nb_samples) {
+            int ch = av_get_channel_layout_nb_channels(src->channel_layout);
+            av_samples_copy(dst->extended_data, src->extended_data, 0, 0,
+                            dst->nb_samples, ch, dst->format);
+        } else {
+            av_image_copy(dst->data, dst->linesize, src->data, src->linesize,
+                          dst->format, dst->width, dst->height);
+        }
+        return 0;
+    }
+
+    /* ref the buffers */
+    for (i = 0; i < FF_ARRAY_ELEMS(src->buf) && src->buf[i]; i++) {
+        dst->buf[i] = av_buffer_ref(src->buf[i]);
+        if (!dst->buf[i]) {
+            ret = AVERROR(ENOMEM);
+            goto fail;
+        }
+    }
+
+    if (src->extended_buf) {
+        dst->extended_buf = av_mallocz(sizeof(*dst->extended_buf) *
+                                       src->nb_extended_buf);
+        if (!dst->extended_buf) {
+            ret = AVERROR(ENOMEM);
+            goto fail;
+        }
+        dst->nb_extended_buf = src->nb_extended_buf;
+
+        for (i = 0; i < src->nb_extended_buf; i++) {
+            dst->extended_buf[i] = av_buffer_ref(src->extended_buf[i]);
+            if (!dst->extended_buf[i]) {
+                ret = AVERROR(ENOMEM);
+                goto fail;
+            }
+        }
+    }
+
+    /* duplicate extended data */
+    if (src->extended_data != src->data) {
+        int ch = av_get_channel_layout_nb_channels(src->channel_layout);
+
+        if (!ch) {
+            ret = AVERROR(EINVAL);
+            goto fail;
+        }
+
+        dst->extended_data = av_malloc(sizeof(*dst->extended_data) * ch);
+        if (!dst->extended_data) {
+            ret = AVERROR(ENOMEM);
+            goto fail;
+        }
+        memcpy(dst->extended_data, src->extended_data, sizeof(*src->extended_data) * ch);
+    } else
+        dst->extended_data = dst->data;
+
+    memcpy(dst->data,     src->data,     sizeof(src->data));
+    memcpy(dst->linesize, src->linesize, sizeof(src->linesize));
+
+    return 0;
+
+fail:
+    av_frame_unref(dst);
+    return ret;
+}
+
+AVFrame *av_frame_clone(AVFrame *src)
+{
+    AVFrame *ret = av_frame_alloc();
+
+    if (!ret)
+        return NULL;
+
+    if (av_frame_ref(ret, src) < 0)
+        av_frame_free(&ret);
+
+    return ret;
+}
+
+void av_frame_unref(AVFrame *frame)
+{
+    int i;
+
+    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++)
+        av_buffer_unref(&frame->extended_buf[i]);
+    av_freep(&frame->extended_buf);
+    get_frame_defaults(frame);
+}
+
+void av_frame_move_ref(AVFrame *dst, AVFrame *src)
+{
+    *dst = *src;
+    if (src->extended_data == src->data)
+        dst->extended_data = dst->data;
+    memset(src, 0, sizeof(*src));
+    get_frame_defaults(src);
+}
+
+int av_frame_is_writable(AVFrame *frame)
+{
+    int i, ret = 1;
+
+    /* assume non-refcounted frames are not writable */
+    if (!frame->buf[0])
+        return 0;
+
+    for (i = 0; i < FF_ARRAY_ELEMS(frame->buf) && frame->buf[i]; i++)
+        ret &= !!av_buffer_is_writable(frame->buf[i]);
+    for (i = 0; i < frame->nb_extended_buf; i++)
+        ret &= !!av_buffer_is_writable(frame->extended_buf[i]);
+
+    return ret;
+}
+
+int av_frame_make_writable(AVFrame *frame)
+{
+    AVFrame tmp;
+    int ret;
+
+    if (!frame->buf[0])
+        return AVERROR(EINVAL);
+
+    if (av_frame_is_writable(frame))
+        return 0;
+
+    memset(&tmp, 0, sizeof(tmp));
+    tmp.format         = frame->format;
+    tmp.width          = frame->width;
+    tmp.height         = frame->height;
+    tmp.channel_layout = frame->channel_layout;
+    tmp.nb_samples     = frame->nb_samples;
+    ret = av_frame_get_buffer(&tmp, 32);
+    if (ret < 0)
+        return ret;
+
+    if (tmp.nb_samples) {
+        int ch = av_get_channel_layout_nb_channels(tmp.channel_layout);
+        av_samples_copy(tmp.extended_data, frame->extended_data, 0, 0,
+                        frame->nb_samples, ch, frame->format);
+    } else {
+        av_image_copy(tmp.data, tmp.linesize, frame->data, frame->linesize,
+                      frame->format, frame->width, frame->height);
+    }
+
+    ret = av_frame_copy_props(&tmp, frame);
+    if (ret < 0) {
+        av_frame_unref(&tmp);
+        return ret;
+    }
+
+    av_frame_unref(frame);
+
+    *frame = tmp;
+    if (tmp.data == tmp.extended_data)
+        frame->extended_data = frame->data;
+
+    return 0;
+}
+
+int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
+{
+    dst->key_frame           = src->key_frame;
+    dst->pict_type           = src->pict_type;
+    dst->sample_aspect_ratio = src->sample_aspect_ratio;
+    dst->pts                 = src->pts;
+    dst->interlaced_frame    = src->interlaced_frame;
+    dst->top_field_first     = src->top_field_first;
+    dst->sample_rate         = src->sample_rate;
+    dst->opaque              = src->opaque;
+    dst->pkt_pts             = src->pkt_pts;
+    dst->pkt_dts             = src->pkt_dts;
+    dst->quality             = src->quality;
+    dst->coded_picture_number = src->coded_picture_number;
+    dst->display_picture_number = src->display_picture_number;
+
+    return 0;
+}
+
+AVBufferRef *av_frame_get_plane_buffer(AVFrame *frame, int plane)
+{
+    uint8_t *data;
+    int planes, i;
+
+    if (frame->nb_samples) {
+        int channels = av_get_channel_layout_nb_channels(frame->channel_layout);
+        if (!channels)
+            return NULL;
+        planes = av_sample_fmt_is_planar(frame->format) ? channels : 1;
+    } else
+        planes = 4;
+
+    if (plane < 0 || plane >= planes || !frame->extended_data[plane])
+        return NULL;
+    data = frame->extended_data[plane];
+
+    for (i = 0; i < FF_ARRAY_ELEMS(frame->buf) && frame->buf[i]; i++) {
+        AVBufferRef *buf = frame->buf[i];
+        if (data >= buf->data && data < buf->data + buf->size)
+            return buf;
+    }
+    for (i = 0; i < frame->nb_extended_buf; i++) {
+        AVBufferRef *buf = frame->extended_buf[i];
+        if (data >= buf->data && data < buf->data + buf->size)
+            return buf;
+    }
+    return NULL;
+}
diff --git a/libavutil/frame.h b/libavutil/frame.h
new file mode 100644
index 0000000000..ed410ba122
--- /dev/null
+++ b/libavutil/frame.h
@@ -0,0 +1,429 @@
+/*
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVUTIL_FRAME_H
+#define AVUTIL_FRAME_H
+
+#include <stdint.h>
+
+#include "libavcodec/version.h"
+
+#include "avutil.h"
+#include "buffer.h"
+#include "rational.h"
+#include "samplefmt.h"
+
+
+/**
+ * This structure describes decoded (raw) audio or video data.
+ *
+ * AVFrame must be allocated using av_frame_alloc(). Not that this only
+ * allocates the AVFrame itself, the buffers for the data must be managed
+ * through other means (see below).
+ * AVFrame must be freed with av_frame_free().
+ *
+ * AVFrame is typically allocated once and then reused multiple times to hold
+ * different data (e.g. a single AVFrame to hold frames received from a
+ * decoder). In such a case, av_frame_unref() will free any references held by
+ * the frame and reset it to its original clean state before it
+ * is reused again.
+ *
+ * The data described by an AVFrame is usually reference counted through the
+ * AVBuffer API. The underlying buffer references are stored in AVFrame.buf /
+ * AVFrame.extended_buf. An AVFrame is considered to be reference counted if at
+ * least one reference is set, i.e. if AVFrame.buf[0] != NULL. In such a case,
+ * every single data plane must be contained in one of the buffers in
+ * AVFrame.buf or AVFrame.extended_buf.
+ * There may be a single buffer for all the data, or one separate buffer for
+ * each plane, or anything in between.
+ *
+ * sizeof(AVFrame) is not a part of the public ABI, so new fields may be added
+ * to the end with a minor bump.
+ */
+typedef struct AVFrame {
+#define AV_NUM_DATA_POINTERS 8
+    /**
+     * pointer to the picture/channel planes.
+     * This might be different from the first allocated byte
+     */
+    uint8_t *data[AV_NUM_DATA_POINTERS];
+
+    /**
+     * For video, size in bytes of each picture line.
+     * For audio, size in bytes of each plane.
+     *
+     * For audio, only linesize[0] may be set. For planar audio, each channel
+     * plane must be the same size.
+     */
+    int linesize[AV_NUM_DATA_POINTERS];
+
+    /**
+     * pointers to the data planes/channels.
+     *
+     * For video, this should simply point to data[].
+     *
+     * For planar audio, each channel has a separate data pointer, and
+     * linesize[0] contains the size of each channel buffer.
+     * For packed audio, there is just one data pointer, and linesize[0]
+     * contains the total size of the buffer for all channels.
+     *
+     * Note: Both data and extended_data should always be set in a valid frame,
+     * but for planar audio with more channels that can fit in data,
+     * extended_data must be used in order to access all channels.
+     */
+    uint8_t **extended_data;
+
+    /**
+     * width and height of the video frame
+     */
+    int width, height;
+
+    /**
+     * number of audio samples (per channel) described by this frame
+     */
+    int nb_samples;
+
+    /**
+     * format of the frame, -1 if unknown or unset
+     * Values correspond to enum AVPixelFormat for video frames,
+     * enum AVSampleFormat for audio)
+     */
+    int format;
+
+    /**
+     * 1 -> keyframe, 0-> not
+     */
+    int key_frame;
+
+    /**
+     * Picture type of the frame.
+     */
+    enum AVPictureType pict_type;
+
+    uint8_t *base[AV_NUM_DATA_POINTERS];
+
+    /**
+     * Sample aspect ratio for the video frame, 0/1 if unknown/unspecified.
+     */
+    AVRational sample_aspect_ratio;
+
+    /**
+     * Presentation timestamp in time_base units (time when frame should be shown to user).
+     */
+    int64_t pts;
+
+    /**
+     * PTS copied from the AVPacket that was decoded to produce this frame.
+     */
+    int64_t pkt_pts;
+
+    /**
+     * DTS copied from the AVPacket that triggered returning this frame.
+     */
+    int64_t pkt_dts;
+
+    /**
+     * picture number in bitstream order
+     */
+    int coded_picture_number;
+    /**
+     * picture number in display order
+     */
+    int display_picture_number;
+
+    /**
+     * quality (between 1 (good) and FF_LAMBDA_MAX (bad))
+     */
+    int quality;
+
+    int reference;
+
+    /**
+     * QP table
+     */
+    int8_t *qscale_table;
+    /**
+     * QP store stride
+     */
+    int qstride;
+
+    int qscale_type;
+
+    /**
+     * mbskip_table[mb]>=1 if MB didn't change
+     * stride= mb_width = (width+15)>>4
+     */
+    uint8_t *mbskip_table;
+
+    /**
+     * motion vector table
+     * @code
+     * example:
+     * int mv_sample_log2= 4 - motion_subsample_log2;
+     * int mb_width= (width+15)>>4;
+     * int mv_stride= (mb_width << mv_sample_log2) + 1;
+     * motion_val[direction][x + y*mv_stride][0->mv_x, 1->mv_y];
+     * @endcode
+     */
+    int16_t (*motion_val[2])[2];
+
+    /**
+     * macroblock type table
+     * mb_type_base + mb_width + 2
+     */
+    uint32_t *mb_type;
+
+    /**
+     * DCT coefficients
+     */
+    short *dct_coeff;
+
+    /**
+     * motion reference frame index
+     * the order in which these are stored can depend on the codec.
+     */
+    int8_t *ref_index[2];
+
+    /**
+     * for some private data of the user
+     */
+    void *opaque;
+
+    /**
+     * error
+     */
+    uint64_t error[AV_NUM_DATA_POINTERS];
+
+    int type;
+
+    /**
+     * When decoding, this signals how much the picture must be delayed.
+     * extra_delay = repeat_pict / (2*fps)
+     */
+    int repeat_pict;
+
+    /**
+     * The content of the picture is interlaced.
+     */
+    int interlaced_frame;
+
+    /**
+     * If the content is interlaced, is top field displayed first.
+     */
+    int top_field_first;
+
+    /**
+     * Tell user application that palette has changed from previous frame.
+     */
+    int palette_has_changed;
+
+    int buffer_hints;
+
+    /**
+     * Pan scan.
+     */
+    struct AVPanScan *pan_scan;
+
+    /**
+     * reordered opaque 64bit (generally an integer or a double precision float
+     * PTS but can be anything).
+     * The user sets AVCodecContext.reordered_opaque to represent the input at
+     * that time,
+     * the decoder reorders values as needed and sets AVFrame.reordered_opaque
+     * to exactly one of the values provided by the user through AVCodecContext.reordered_opaque
+     * @deprecated in favor of pkt_pts
+     */
+    int64_t reordered_opaque;
+
+#if FF_API_AVFRAME_LAVC
+    /**
+     * @deprecated this field is unused
+     */
+    attribute_deprecated void *hwaccel_picture_private;
+#endif
+
+    struct AVCodecContext *owner;
+    void *thread_opaque;
+
+    /**
+     * log2 of the size of the block which a single vector in motion_val represents:
+     * (4->16x16, 3->8x8, 2-> 4x4, 1-> 2x2)
+     */
+    uint8_t motion_subsample_log2;
+
+    /**
+     * Sample rate of the audio data.
+     */
+    int sample_rate;
+
+    /**
+     * Channel layout of the audio data.
+     */
+    uint64_t channel_layout;
+
+    /**
+     * AVBuffer references backing the data for this frame. If all elements of
+     * this array are NULL, then this frame is not reference counted.
+     *
+     * There may be at most one AVBuffer per data plane, so for video this array
+     * always contains all the references. For planar audio with more than
+     * AV_NUM_DATA_POINTERS channels, there may be more buffers than can fit in
+     * this array. Then the extra AVBufferRef pointers are stored in the
+     * extended_buf array.
+     */
+    AVBufferRef *buf[AV_NUM_DATA_POINTERS];
+
+    /**
+     * For planar audio which requires more than AV_NUM_DATA_POINTERS
+     * AVBufferRef pointers, this array will hold all the references which
+     * cannot fit into AVFrame.buf.
+     *
+     * Note that this is different from AVFrame.extended_data, which always
+     * contains all the pointers. This array only contains the extra pointers,
+     * which cannot fit into AVFrame.buf.
+     *
+     * This array is always allocated using av_malloc() by whoever constructs
+     * the frame. It is freed in av_frame_unref().
+     */
+    AVBufferRef **extended_buf;
+    /**
+     * Number of elements in extended_buf.
+     */
+    int        nb_extended_buf;
+} AVFrame;
+
+/**
+ * Allocate an AVFrame and set its fields to default values.  The resulting
+ * struct must be freed using av_frame_free().
+ *
+ * @return An AVFrame filled with default values or NULL on failure.
+ *
+ * @note this only allocates the AVFrame itself, not the data buffers. Those
+ * must be allocated through other means, e.g. with av_frame_get_buffer() or
+ * manually.
+ */
+AVFrame *av_frame_alloc(void);
+
+/**
+ * Free the frame and any dynamically allocated objects in it,
+ * e.g. extended_data. If the frame is reference counted, it will be
+ * unreferenced first.
+ *
+ * @param frame frame to be freed. The pointer will be set to NULL.
+ */
+void av_frame_free(AVFrame **frame);
+
+/**
+ * Setup a new reference to the data described by an given frame.
+ *
+ * Copy frame properties from src to dst and create a new reference for each
+ * AVBufferRef from src.
+ *
+ * If src is not reference counted, new buffers are allocated and the data is
+ * copied.
+ *
+ * @return 0 on success, a negative AVERROR on error
+ */
+int av_frame_ref(AVFrame *dst, AVFrame *src);
+
+/**
+ * Create a new frame that references the same data as src.
+ *
+ * This is a shortcut for av_frame_alloc()+av_frame_ref().
+ *
+ * @return newly created AVFrame on success, NULL on error.
+ */
+AVFrame *av_frame_clone(AVFrame *src);
+
+/**
+ * Unreference all the buffers referenced by frame and reset the frame fields.
+ */
+void av_frame_unref(AVFrame *frame);
+
+/**
+ * Move everythnig contained in src to dst and reset src.
+ */
+void av_frame_move_ref(AVFrame *dst, AVFrame *src);
+
+/**
+ * Allocate new buffer(s) for audio or video data.
+ *
+ * The following fields must be set on frame before calling this function:
+ * - format (pixel format for video, sample format for audio)
+ * - width and height for video
+ * - nb_samples and channel_layout for audio
+ *
+ * This function will fill AVFrame.data and AVFrame.buf arrays and, if
+ * necessary, allocate and fill AVFrame.extended_data and AVFrame.extended_buf.
+ * For planar formats, one buffer will be allocated for each plane.
+ *
+ * @param frame frame in which to store the new buffers.
+ * @param align required buffer size alignment
+ *
+ * @return 0 on success, a negative AVERROR on error.
+ */
+int av_frame_get_buffer(AVFrame *frame, int align);
+
+/**
+ * Check if the frame data is writable.
+ *
+ * @return A positive value if the frame data is writable (which is true if and
+ * only if each of the underlying buffers has only one reference, namely the one
+ * stored in this frame). Return 0 otherwise.
+ *
+ * If 1 is returned the answer is valid until av_buffer_ref() is called on any
+ * of the underlying AVBufferRefs (e.g. through av_frame_ref() or directly).
+ *
+ * @see av_frame_make_writable(), av_buffer_is_writable()
+ */
+int av_frame_is_writable(AVFrame *frame);
+
+/**
+ * Ensure that the frame data is writable, avoiding data copy if possible.
+ *
+ * Do nothing if the frame is writable, allocate new buffers and copy the data
+ * if it is not.
+ *
+ * @return 0 on success, a negative AVERROR on error.
+ *
+ * @see av_frame_is_writable(), av_buffer_is_writable(),
+ * av_buffer_make_writable()
+ */
+int av_frame_make_writable(AVFrame *frame);
+
+/**
+ * Copy only "metadata" fields from src to dst.
+ *
+ * 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.
+ */
+int av_frame_copy_props(AVFrame *dst, const AVFrame *src);
+
+/**
+ * Get the buffer reference a given data plane is stored in.
+ *
+ * @param plane index of the data plane of interest in frame->extended_data.
+ *
+ * @return the buffer reference that contains the plane or NULL if the input
+ * frame is not valid.
+ */
+AVBufferRef *av_frame_get_plane_buffer(AVFrame *frame, int plane);
+
+#endif /* AVUTIL_FRAME_H */