yading@11: /*
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "channel_layout.h"
yading@11: #include "avassert.h"
yading@11: #include "buffer.h"
yading@11: #include "common.h"
yading@11: #include "dict.h"
yading@11: #include "frame.h"
yading@11: #include "imgutils.h"
yading@11: #include "mem.h"
yading@11: #include "samplefmt.h"
yading@11: 
yading@11: #define MAKE_ACCESSORS(str, name, type, field) \
yading@11:     type av_##name##_get_##field(const str *s) { return s->field; } \
yading@11:     void av_##name##_set_##field(str *s, type v) { s->field = v; }
yading@11: 
yading@11: MAKE_ACCESSORS(AVFrame, frame, int64_t, best_effort_timestamp)
yading@11: MAKE_ACCESSORS(AVFrame, frame, int64_t, pkt_duration)
yading@11: MAKE_ACCESSORS(AVFrame, frame, int64_t, pkt_pos)
yading@11: MAKE_ACCESSORS(AVFrame, frame, int64_t, channel_layout)
yading@11: MAKE_ACCESSORS(AVFrame, frame, int,     channels)
yading@11: MAKE_ACCESSORS(AVFrame, frame, int,     sample_rate)
yading@11: MAKE_ACCESSORS(AVFrame, frame, AVDictionary *, metadata)
yading@11: MAKE_ACCESSORS(AVFrame, frame, int,     decode_error_flags)
yading@11: MAKE_ACCESSORS(AVFrame, frame, int,     pkt_size)
yading@11: 
yading@11: #define CHECK_CHANNELS_CONSISTENCY(frame) \
yading@11:     av_assert2(!(frame)->channel_layout || \
yading@11:                (frame)->channels == \
yading@11:                av_get_channel_layout_nb_channels((frame)->channel_layout))
yading@11: 
yading@11: AVDictionary **avpriv_frame_get_metadatap(AVFrame *frame) {return &frame->metadata;};
yading@11: 
yading@11: int av_frame_set_qp_table(AVFrame *f, AVBufferRef *buf, int stride, int qp_type)
yading@11: {
yading@11:     av_buffer_unref(&f->qp_table_buf);
yading@11: 
yading@11:     f->qp_table_buf = buf;
yading@11: 
yading@11:     f->qscale_table = buf->data;
yading@11:     f->qstride      = stride;
yading@11:     f->qscale_type  = qp_type;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: int8_t *av_frame_get_qp_table(AVFrame *f, int *stride, int *type)
yading@11: {
yading@11:     *stride = f->qstride;
yading@11:     *type   = f->qscale_type;
yading@11: 
yading@11:     if (!f->qp_table_buf)
yading@11:         return NULL;
yading@11: 
yading@11:     return f->qp_table_buf->data;
yading@11: }
yading@11: 
yading@11: static void get_frame_defaults(AVFrame *frame)
yading@11: {
yading@11:     if (frame->extended_data != frame->data)
yading@11:         av_freep(&frame->extended_data);
yading@11: 
yading@11:     memset(frame, 0, sizeof(*frame));
yading@11: 
yading@11:     frame->pts                   =
yading@11:     frame->pkt_dts               =
yading@11:     frame->pkt_pts               = AV_NOPTS_VALUE;
yading@11:     av_frame_set_best_effort_timestamp(frame, AV_NOPTS_VALUE);
yading@11:     av_frame_set_pkt_duration         (frame, 0);
yading@11:     av_frame_set_pkt_pos              (frame, -1);
yading@11:     av_frame_set_pkt_size             (frame, -1);
yading@11:     frame->key_frame           = 1;
yading@11:     frame->sample_aspect_ratio = (AVRational){ 0, 1 };
yading@11:     frame->format              = -1; /* unknown */
yading@11:     frame->extended_data       = frame->data;
yading@11: }
yading@11: 
yading@11: AVFrame *av_frame_alloc(void)
yading@11: {
yading@11:     AVFrame *frame = av_mallocz(sizeof(*frame));
yading@11: 
yading@11:     if (!frame)
yading@11:         return NULL;
yading@11: 
yading@11:     frame->extended_data = NULL;
yading@11:     get_frame_defaults(frame);
yading@11: 
yading@11:     return frame;
yading@11: }
yading@11: 
yading@11: void av_frame_free(AVFrame **frame)
yading@11: {
yading@11:     if (!frame || !*frame)
yading@11:         return;
yading@11: 
yading@11:     av_frame_unref(*frame);
yading@11:     av_freep(frame);
yading@11: }
yading@11: 
yading@11: static int get_video_buffer(AVFrame *frame, int align)
yading@11: {
yading@11:     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
yading@11:     int ret, i;
yading@11: 
yading@11:     if (!desc)
yading@11:         return AVERROR(EINVAL);
yading@11: 
yading@11:     if ((ret = av_image_check_size(frame->width, frame->height, 0, NULL)) < 0)
yading@11:         return ret;
yading@11: 
yading@11:     if (!frame->linesize[0]) {
yading@11:         ret = av_image_fill_linesizes(frame->linesize, frame->format,
yading@11:                                       frame->width);
yading@11:         if (ret < 0)
yading@11:             return ret;
yading@11: 
yading@11:         for (i = 0; i < 4 && frame->linesize[i]; i++)
yading@11:             frame->linesize[i] = FFALIGN(frame->linesize[i], align);
yading@11:     }
yading@11: 
yading@11:     for (i = 0; i < 4 && frame->linesize[i]; i++) {
yading@11:         int h = FFALIGN(frame->height, 32);
yading@11:         if (i == 1 || i == 2)
yading@11:             h = -((-h) >> desc->log2_chroma_h);
yading@11: 
yading@11:         frame->buf[i] = av_buffer_alloc(frame->linesize[i] * h + 16);
yading@11:         if (!frame->buf[i])
yading@11:             goto fail;
yading@11: 
yading@11:         frame->data[i] = frame->buf[i]->data;
yading@11:     }
yading@11:     if (desc->flags & PIX_FMT_PAL || desc->flags & PIX_FMT_PSEUDOPAL) {
yading@11:         av_buffer_unref(&frame->buf[1]);
yading@11:         frame->buf[1] = av_buffer_alloc(1024);
yading@11:         if (!frame->buf[1])
yading@11:             goto fail;
yading@11:         frame->data[1] = frame->buf[1]->data;
yading@11:     }
yading@11: 
yading@11:     frame->extended_data = frame->data;
yading@11: 
yading@11:     return 0;
yading@11: fail:
yading@11:     av_frame_unref(frame);
yading@11:     return AVERROR(ENOMEM);
yading@11: }
yading@11: 
yading@11: static int get_audio_buffer(AVFrame *frame, int align)
yading@11: {
yading@11:     int channels = frame->channels;
yading@11:     int planar   = av_sample_fmt_is_planar(frame->format);
yading@11:     int planes   = planar ? channels : 1;
yading@11:     int ret, i;
yading@11: 
yading@11:     CHECK_CHANNELS_CONSISTENCY(frame);
yading@11:     if (!frame->linesize[0]) {
yading@11:         ret = av_samples_get_buffer_size(&frame->linesize[0], channels,
yading@11:                                          frame->nb_samples, frame->format,
yading@11:                                          align);
yading@11:         if (ret < 0)
yading@11:             return ret;
yading@11:     }
yading@11: 
yading@11:     if (planes > AV_NUM_DATA_POINTERS) {
yading@11:         frame->extended_data = av_mallocz(planes *
yading@11:                                           sizeof(*frame->extended_data));
yading@11:         frame->extended_buf  = av_mallocz((planes - AV_NUM_DATA_POINTERS) *
yading@11:                                           sizeof(*frame->extended_buf));
yading@11:         if (!frame->extended_data || !frame->extended_buf) {
yading@11:             av_freep(&frame->extended_data);
yading@11:             av_freep(&frame->extended_buf);
yading@11:             return AVERROR(ENOMEM);
yading@11:         }
yading@11:         frame->nb_extended_buf = planes - AV_NUM_DATA_POINTERS;
yading@11:     } else
yading@11:         frame->extended_data = frame->data;
yading@11: 
yading@11:     for (i = 0; i < FFMIN(planes, AV_NUM_DATA_POINTERS); i++) {
yading@11:         frame->buf[i] = av_buffer_alloc(frame->linesize[0]);
yading@11:         if (!frame->buf[i]) {
yading@11:             av_frame_unref(frame);
yading@11:             return AVERROR(ENOMEM);
yading@11:         }
yading@11:         frame->extended_data[i] = frame->data[i] = frame->buf[i]->data;
yading@11:     }
yading@11:     for (i = 0; i < planes - AV_NUM_DATA_POINTERS; i++) {
yading@11:         frame->extended_buf[i] = av_buffer_alloc(frame->linesize[0]);
yading@11:         if (!frame->extended_buf[i]) {
yading@11:             av_frame_unref(frame);
yading@11:             return AVERROR(ENOMEM);
yading@11:         }
yading@11:         frame->extended_data[i + AV_NUM_DATA_POINTERS] = frame->extended_buf[i]->data;
yading@11:     }
yading@11:     return 0;
yading@11: 
yading@11: }
yading@11: 
yading@11: int av_frame_get_buffer(AVFrame *frame, int align)
yading@11: {
yading@11:     if (frame->format < 0)
yading@11:         return AVERROR(EINVAL);
yading@11: 
yading@11:     if (frame->width > 0 && frame->height > 0)
yading@11:         return get_video_buffer(frame, align);
yading@11:     else if (frame->nb_samples > 0 && frame->channel_layout)
yading@11:         return get_audio_buffer(frame, align);
yading@11: 
yading@11:     return AVERROR(EINVAL);
yading@11: }
yading@11: 
yading@11: int av_frame_ref(AVFrame *dst, AVFrame *src)
yading@11: {
yading@11:     int i, ret = 0;
yading@11: 
yading@11:     dst->format         = src->format;
yading@11:     dst->width          = src->width;
yading@11:     dst->height         = src->height;
yading@11:     dst->channels       = src->channels;
yading@11:     dst->channel_layout = src->channel_layout;
yading@11:     dst->nb_samples     = src->nb_samples;
yading@11: 
yading@11:     ret = av_frame_copy_props(dst, src);
yading@11:     if (ret < 0)
yading@11:         return ret;
yading@11: 
yading@11:     /* duplicate the frame data if it's not refcounted */
yading@11:     if (!src->buf[0]) {
yading@11:         ret = av_frame_get_buffer(dst, 32);
yading@11:         if (ret < 0)
yading@11:             return ret;
yading@11: 
yading@11:         if (src->nb_samples) {
yading@11:             int ch = src->channels;
yading@11:             CHECK_CHANNELS_CONSISTENCY(src);
yading@11:             av_samples_copy(dst->extended_data, src->extended_data, 0, 0,
yading@11:                             dst->nb_samples, ch, dst->format);
yading@11:         } else {
yading@11:             av_image_copy(dst->data, dst->linesize, src->data, src->linesize,
yading@11:                           dst->format, dst->width, dst->height);
yading@11:         }
yading@11:         return 0;
yading@11:     }
yading@11: 
yading@11:     /* ref the buffers */
yading@11:     for (i = 0; i < FF_ARRAY_ELEMS(src->buf) && src->buf[i]; i++) {
yading@11:         dst->buf[i] = av_buffer_ref(src->buf[i]);
yading@11:         if (!dst->buf[i]) {
yading@11:             ret = AVERROR(ENOMEM);
yading@11:             goto fail;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     if (src->extended_buf) {
yading@11:         dst->extended_buf = av_mallocz(sizeof(*dst->extended_buf) *
yading@11:                                        src->nb_extended_buf);
yading@11:         if (!dst->extended_buf) {
yading@11:             ret = AVERROR(ENOMEM);
yading@11:             goto fail;
yading@11:         }
yading@11:         dst->nb_extended_buf = src->nb_extended_buf;
yading@11: 
yading@11:         for (i = 0; i < src->nb_extended_buf; i++) {
yading@11:             dst->extended_buf[i] = av_buffer_ref(src->extended_buf[i]);
yading@11:             if (!dst->extended_buf[i]) {
yading@11:                 ret = AVERROR(ENOMEM);
yading@11:                 goto fail;
yading@11:             }
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     /* duplicate extended data */
yading@11:     if (src->extended_data != src->data) {
yading@11:         int ch = src->channels;
yading@11: 
yading@11:         if (!ch) {
yading@11:             ret = AVERROR(EINVAL);
yading@11:             goto fail;
yading@11:         }
yading@11:         CHECK_CHANNELS_CONSISTENCY(src);
yading@11: 
yading@11:         dst->extended_data = av_malloc(sizeof(*dst->extended_data) * ch);
yading@11:         if (!dst->extended_data) {
yading@11:             ret = AVERROR(ENOMEM);
yading@11:             goto fail;
yading@11:         }
yading@11:         memcpy(dst->extended_data, src->extended_data, sizeof(*src->extended_data) * ch);
yading@11:     } else
yading@11:         dst->extended_data = dst->data;
yading@11: 
yading@11:     memcpy(dst->data,     src->data,     sizeof(src->data));
yading@11:     memcpy(dst->linesize, src->linesize, sizeof(src->linesize));
yading@11: 
yading@11:     return 0;
yading@11: 
yading@11: fail:
yading@11:     av_frame_unref(dst);
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: AVFrame *av_frame_clone(AVFrame *src)
yading@11: {
yading@11:     AVFrame *ret = av_frame_alloc();
yading@11: 
yading@11:     if (!ret)
yading@11:         return NULL;
yading@11: 
yading@11:     if (av_frame_ref(ret, src) < 0)
yading@11:         av_frame_free(&ret);
yading@11: 
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: void av_frame_unref(AVFrame *frame)
yading@11: {
yading@11:     int i;
yading@11: 
yading@11:     for (i = 0; i < frame->nb_side_data; i++) {
yading@11:         av_freep(&frame->side_data[i]->data);
yading@11:         av_dict_free(&frame->side_data[i]->metadata);
yading@11:         av_freep(&frame->side_data[i]);
yading@11:     }
yading@11:     av_freep(&frame->side_data);
yading@11: 
yading@11:     for (i = 0; i < FF_ARRAY_ELEMS(frame->buf); i++)
yading@11:         av_buffer_unref(&frame->buf[i]);
yading@11:     for (i = 0; i < frame->nb_extended_buf; i++)
yading@11:         av_buffer_unref(&frame->extended_buf[i]);
yading@11:     av_freep(&frame->extended_buf);
yading@11:     av_dict_free(&frame->metadata);
yading@11:     av_buffer_unref(&frame->qp_table_buf);
yading@11: 
yading@11:     get_frame_defaults(frame);
yading@11: }
yading@11: 
yading@11: void av_frame_move_ref(AVFrame *dst, AVFrame *src)
yading@11: {
yading@11:     *dst = *src;
yading@11:     if (src->extended_data == src->data)
yading@11:         dst->extended_data = dst->data;
yading@11:     memset(src, 0, sizeof(*src));
yading@11:     get_frame_defaults(src);
yading@11: }
yading@11: 
yading@11: int av_frame_is_writable(AVFrame *frame)
yading@11: {
yading@11:     int i, ret = 1;
yading@11: 
yading@11:     /* assume non-refcounted frames are not writable */
yading@11:     if (!frame->buf[0])
yading@11:         return 0;
yading@11: 
yading@11:     for (i = 0; i < FF_ARRAY_ELEMS(frame->buf) && frame->buf[i]; i++)
yading@11:         ret &= !!av_buffer_is_writable(frame->buf[i]);
yading@11:     for (i = 0; i < frame->nb_extended_buf; i++)
yading@11:         ret &= !!av_buffer_is_writable(frame->extended_buf[i]);
yading@11: 
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: int av_frame_make_writable(AVFrame *frame)
yading@11: {
yading@11:     AVFrame tmp;
yading@11:     int ret;
yading@11: 
yading@11:     if (!frame->buf[0])
yading@11:         return AVERROR(EINVAL);
yading@11: 
yading@11:     if (av_frame_is_writable(frame))
yading@11:         return 0;
yading@11: 
yading@11:     memset(&tmp, 0, sizeof(tmp));
yading@11:     tmp.format         = frame->format;
yading@11:     tmp.width          = frame->width;
yading@11:     tmp.height         = frame->height;
yading@11:     tmp.channels       = frame->channels;
yading@11:     tmp.channel_layout = frame->channel_layout;
yading@11:     tmp.nb_samples     = frame->nb_samples;
yading@11:     ret = av_frame_get_buffer(&tmp, 32);
yading@11:     if (ret < 0)
yading@11:         return ret;
yading@11: 
yading@11:     if (tmp.nb_samples) {
yading@11:         int ch = tmp.channels;
yading@11:         CHECK_CHANNELS_CONSISTENCY(&tmp);
yading@11:         av_samples_copy(tmp.extended_data, frame->extended_data, 0, 0,
yading@11:                         frame->nb_samples, ch, frame->format);
yading@11:     } else {
yading@11:         av_image_copy(tmp.data, tmp.linesize, frame->data, frame->linesize,
yading@11:                       frame->format, frame->width, frame->height);
yading@11:     }
yading@11: 
yading@11:     ret = av_frame_copy_props(&tmp, frame);
yading@11:     if (ret < 0) {
yading@11:         av_frame_unref(&tmp);
yading@11:         return ret;
yading@11:     }
yading@11: 
yading@11:     av_frame_unref(frame);
yading@11: 
yading@11:     *frame = tmp;
yading@11:     if (tmp.data == tmp.extended_data)
yading@11:         frame->extended_data = frame->data;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
yading@11: {
yading@11:     int i;
yading@11: 
yading@11:     dst->key_frame           = src->key_frame;
yading@11:     dst->pict_type           = src->pict_type;
yading@11:     dst->sample_aspect_ratio = src->sample_aspect_ratio;
yading@11:     dst->pts                 = src->pts;
yading@11:     dst->repeat_pict         = src->repeat_pict;
yading@11:     dst->interlaced_frame    = src->interlaced_frame;
yading@11:     dst->top_field_first     = src->top_field_first;
yading@11:     dst->palette_has_changed = src->palette_has_changed;
yading@11:     dst->sample_rate         = src->sample_rate;
yading@11:     dst->opaque              = src->opaque;
yading@11: #if FF_API_AVFRAME_LAVC
yading@11:     dst->type                = src->type;
yading@11: #endif
yading@11:     dst->pkt_pts             = src->pkt_pts;
yading@11:     dst->pkt_dts             = src->pkt_dts;
yading@11:     dst->pkt_pos             = src->pkt_pos;
yading@11:     dst->pkt_size            = src->pkt_size;
yading@11:     dst->pkt_duration        = src->pkt_duration;
yading@11:     dst->reordered_opaque    = src->reordered_opaque;
yading@11:     dst->quality             = src->quality;
yading@11:     dst->best_effort_timestamp = src->best_effort_timestamp;
yading@11:     dst->coded_picture_number = src->coded_picture_number;
yading@11:     dst->display_picture_number = src->display_picture_number;
yading@11:     dst->decode_error_flags  = src->decode_error_flags;
yading@11: 
yading@11:     av_dict_copy(&dst->metadata, src->metadata, 0);
yading@11: 
yading@11:     memcpy(dst->error, src->error, sizeof(dst->error));
yading@11: 
yading@11:     for (i = 0; i < src->nb_side_data; i++) {
yading@11:         const AVFrameSideData *sd_src = src->side_data[i];
yading@11:         AVFrameSideData *sd_dst = av_frame_new_side_data(dst, sd_src->type,
yading@11:                                                          sd_src->size);
yading@11:         if (!sd_dst) {
yading@11:             for (i = 0; i < dst->nb_side_data; i++) {
yading@11:                 av_freep(&dst->side_data[i]->data);
yading@11:                 av_freep(&dst->side_data[i]);
yading@11:                 av_dict_free(&dst->side_data[i]->metadata);
yading@11:             }
yading@11:             av_freep(&dst->side_data);
yading@11:             return AVERROR(ENOMEM);
yading@11:         }
yading@11:         memcpy(sd_dst->data, sd_src->data, sd_src->size);
yading@11:         av_dict_copy(&sd_dst->metadata, sd_src->metadata, 0);
yading@11:     }
yading@11: 
yading@11:     dst->qscale_table = NULL;
yading@11:     dst->qstride      = 0;
yading@11:     dst->qscale_type  = 0;
yading@11:     if (src->qp_table_buf) {
yading@11:         dst->qp_table_buf = av_buffer_ref(src->qp_table_buf);
yading@11:         if (dst->qp_table_buf) {
yading@11:             dst->qscale_table = dst->qp_table_buf->data;
yading@11:             dst->qstride      = src->qstride;
yading@11:             dst->qscale_type  = src->qscale_type;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: AVBufferRef *av_frame_get_plane_buffer(AVFrame *frame, int plane)
yading@11: {
yading@11:     uint8_t *data;
yading@11:     int planes, i;
yading@11: 
yading@11:     if (frame->nb_samples) {
yading@11:         int channels = frame->channels;
yading@11:         if (!channels)
yading@11:             return NULL;
yading@11:         CHECK_CHANNELS_CONSISTENCY(frame);
yading@11:         planes = av_sample_fmt_is_planar(frame->format) ? channels : 1;
yading@11:     } else
yading@11:         planes = 4;
yading@11: 
yading@11:     if (plane < 0 || plane >= planes || !frame->extended_data[plane])
yading@11:         return NULL;
yading@11:     data = frame->extended_data[plane];
yading@11: 
yading@11:     for (i = 0; i < FF_ARRAY_ELEMS(frame->buf) && frame->buf[i]; i++) {
yading@11:         AVBufferRef *buf = frame->buf[i];
yading@11:         if (data >= buf->data && data < buf->data + buf->size)
yading@11:             return buf;
yading@11:     }
yading@11:     for (i = 0; i < frame->nb_extended_buf; i++) {
yading@11:         AVBufferRef *buf = frame->extended_buf[i];
yading@11:         if (data >= buf->data && data < buf->data + buf->size)
yading@11:             return buf;
yading@11:     }
yading@11:     return NULL;
yading@11: }
yading@11: 
yading@11: AVFrameSideData *av_frame_new_side_data(AVFrame *frame,
yading@11:                                         enum AVFrameSideDataType type,
yading@11:                                         int size)
yading@11: {
yading@11:     AVFrameSideData *ret, **tmp;
yading@11: 
yading@11:     if (frame->nb_side_data > INT_MAX / sizeof(*frame->side_data) - 1)
yading@11:         return NULL;
yading@11: 
yading@11:     tmp = av_realloc(frame->side_data,
yading@11:                      (frame->nb_side_data + 1) * sizeof(*frame->side_data));
yading@11:     if (!tmp)
yading@11:         return NULL;
yading@11:     frame->side_data = tmp;
yading@11: 
yading@11:     ret = av_mallocz(sizeof(*ret));
yading@11:     if (!ret)
yading@11:         return NULL;
yading@11: 
yading@11:     ret->data = av_malloc(size);
yading@11:     if (!ret->data) {
yading@11:         av_freep(&ret);
yading@11:         return NULL;
yading@11:     }
yading@11: 
yading@11:     ret->size = size;
yading@11:     ret->type = type;
yading@11: 
yading@11:     frame->side_data[frame->nb_side_data++] = ret;
yading@11: 
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: AVFrameSideData *av_frame_get_side_data(AVFrame *frame,
yading@11:                                         enum AVFrameSideDataType type)
yading@11: {
yading@11:     int i;
yading@11: 
yading@11:     for (i = 0; i < frame->nb_side_data; i++) {
yading@11:         if (frame->side_data[i]->type == type)
yading@11:             return frame->side_data[i];
yading@11:     }
yading@11:     return NULL;
yading@11: }