mpv/sub/img_convert.c

/*
 * This file is part of mplayer.
 *
 * mplayer is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * mplayer 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with mplayer.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <string.h>
#include <assert.h>

#include <libavutil/mem.h>
#include <libavutil/common.h>

#include "talloc.h"

#include "img_convert.h"
#include "sub.h"
#include "video/img_format.h"
#include "video/mp_image.h"
#include "video/sws_utils.h"
#include "video/memcpy_pic.h"

struct osd_conv_cache {
    struct sub_bitmap part;
    struct sub_bitmap *parts;
};

struct osd_conv_cache *osd_conv_cache_new(void)
{
    return talloc_zero(NULL, struct osd_conv_cache);
}

static void rgba_to_premultiplied_rgba(uint32_t *colors, size_t count)
{
    for (int n = 0; n < count; n++) {
        uint32_t c = colors[n];
        int b = c & 0xFF;
        int g = (c >> 8) & 0xFF;
        int r = (c >> 16) & 0xFF;
        int a = (c >> 24) & 0xFF;
        b = b * a / 255;
        g = g * a / 255;
        r = r * a / 255;
        colors[n] = b | (g << 8) | (r << 16) | (a << 24);
    }
}

bool osd_conv_idx_to_rgba(struct osd_conv_cache *c, struct sub_bitmaps *imgs)
{
    struct sub_bitmaps src = *imgs;
    if (src.format != SUBBITMAP_INDEXED)
        return false;

    imgs->format = SUBBITMAP_RGBA;
    talloc_free(c->parts);
    imgs->parts = c->parts = talloc_array(c, struct sub_bitmap, src.num_parts);

    for (int n = 0; n < src.num_parts; n++) {
        struct sub_bitmap *d = &imgs->parts[n];
        struct sub_bitmap *s = &src.parts[n];
        struct osd_bmp_indexed sb = *(struct osd_bmp_indexed *)s->bitmap;

        rgba_to_premultiplied_rgba(sb.palette, 256);

        *d = *s;
        struct mp_image *image = alloc_mpi(s->w, s->h, IMGFMT_BGRA);
        talloc_steal(c->parts, image);
        d->stride = image->stride[0];
        d->bitmap = image->planes[0];

        for (int y = 0; y < s->h; y++) {
            uint8_t *inbmp = sb.bitmap + y * s->stride;
            uint32_t *outbmp = (uint32_t*)((uint8_t*)d->bitmap + y * d->stride);
            for (int x = 0; x < s->w; x++)
                *outbmp++ = sb.palette[*inbmp++];
        }
    }
    return true;
}

bool osd_conv_blur_rgba(struct osd_conv_cache *c, struct sub_bitmaps *imgs,
                        double gblur)
{
    struct sub_bitmaps src = *imgs;
    if (src.format != SUBBITMAP_RGBA)
        return false;

    talloc_free(c->parts);
    imgs->parts = c->parts = talloc_array(c, struct sub_bitmap, src.num_parts);

    for (int n = 0; n < src.num_parts; n++) {
        struct sub_bitmap *d = &imgs->parts[n];
        struct sub_bitmap *s = &src.parts[n];

        // add a transparent padding border to reduce artifacts
        int pad = 5;
        struct mp_image *temp = alloc_mpi(s->w + pad * 2, s->h + pad * 2,
                                          IMGFMT_BGRA);
        memset_pic(temp->planes[0], 0, temp->w * 4, temp->h, temp->stride[0]);
        uint8_t *p0 = temp->planes[0] + pad * 4 + pad * temp->stride[0];
        memcpy_pic(p0, s->bitmap, s->w * 4, s->h, temp->stride[0], s->stride);

        double sx = (double)s->dw / s->w;
        double sy = (double)s->dh / s->h;

        d->x = s->x - pad * sx;
        d->y = s->y - pad * sy;
        d->w = d->dw = s->dw + pad * 2 * sx;
        d->h = d->dh = s->dh + pad * 2 * sy;
        struct mp_image *image = alloc_mpi(d->w, d->h, IMGFMT_BGRA);
        talloc_steal(c->parts, image);
        d->stride = image->stride[0];
        d->bitmap = image->planes[0];

        mp_image_sw_blur_scale(image, temp, gblur);

        talloc_free(temp);
    }
    return true;
}

static void rgba_to_gray(uint32_t *colors, size_t count)
{
    for (int n = 0; n < count; n++) {
        uint32_t c = colors[n];
        int b = c & 0xFF;
        int g = (c >> 8) & 0xFF;
        int r = (c >> 16) & 0xFF;
        int a = (c >> 24) & 0xFF;
        r = g = b = (r + g + b) / 3;
        colors[n] = b | (g << 8) | (r << 16) | (a << 24);
    }
}

bool osd_conv_idx_to_gray(struct osd_conv_cache *c, struct sub_bitmaps *imgs)
{
    struct sub_bitmaps src = *imgs;
    if (src.format != SUBBITMAP_INDEXED)
        return false;

    talloc_free(c->parts);
    imgs->parts = c->parts = talloc_array(c, struct sub_bitmap, src.num_parts);

    for (int n = 0; n < src.num_parts; n++) {
        struct sub_bitmap *d = &imgs->parts[n];
        struct sub_bitmap *s = &src.parts[n];
        struct osd_bmp_indexed sb = *(struct osd_bmp_indexed *)s->bitmap;

        rgba_to_gray(sb.palette, 256);

        *d = *s;
        d->bitmap = talloc_memdup(c->parts, &sb, sizeof(sb));
    }
    return true;
}