Function copy_from

libavcodec/interplayvideo.c:78–103

} IpvideoContext;

static int copy_from(IpvideoContext *s, AVFrame *src, AVFrame *dst, int delta_x, int delta_y)
{
    int width = dst->width;
    int current_offset = s->pixel_ptr - dst->data[0];
    int x = (current_offset % dst->linesize[0]) / (1 + s->is_16bpp);
    int y = current_offset / dst->linesize[0];
    int dx = delta_x + x - ((delta_x + x >= width) - (delta_x + x < 0)) * width;
    int dy = delta_y + y + (delta_x + x >= width) - (delta_x + x < 0);
    int motion_offset = dy * src->linesize[0] + dx * (1 + s->is_16bpp);

    if (motion_offset < 0) {
        av_log(s->avctx, AV_LOG_ERROR, "motion offset < 0 (%d)\n", motion_offset);
        return AVERROR_INVALIDDATA;
    } else if (motion_offset > s->upper_motion_limit_offset) {
        av_log(s->avctx, AV_LOG_ERROR, "motion offset above limit (%d >= %d)\n",
            motion_offset, s->upper_motion_limit_offset);
        return AVERROR_INVALIDDATA;
    }
    if (!src->data[0]) {
        av_log(s->avctx, AV_LOG_ERROR, "Invalid decode type, corrupted header?\n");
        return AVERROR(EINVAL);
    }
    s->hdsp.put_pixels_tab[!s->is_16bpp][0](s->pixel_ptr, src->data[0] + motion_offset,
                                            dst->linesize[0], 8);
    return 0;
}

static int ipvideo_decode_block_opcode_0x0(IpvideoContext *s, AVFrame *frame)
{