FFmpeg/libavutil/frame.c

/*
 *
 * 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;
}