Move AVFrame from lavc to lavu.

Add AVBuffer-based reference counting API to it.

1 files changed, 429 insertions, 0 deletions

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 */