libwebpenc_common.h

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/*
 * WebP encoding support via libwebp
 * Copyright (c) 2013 Justin Ruggles <justin.ruggles@gmail.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * WebP encoder using libwebp: common structs and methods.
 */

#ifndef AVCODEC_LIBWEBPENC_COMMON_H
#define AVCODEC_LIBWEBPENC_COMMON_H

#include <webp/encode.h>

#include "libavutil/common.h"
#include "libavutil/frame.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "internal.h"

typedef struct LibWebPContextCommon {
    AVClass *class;         // class for AVOptions
    float quality;          // lossy quality 0 - 100
    int lossless;           // use lossless encoding
    int preset;             // configuration preset
    int chroma_warning;     // chroma linesize mismatch warning has been printed
    int conversion_warning; // pixel format conversion warning has been printed
    WebPConfig config;      // libwebp configuration
    AVFrame *ref;
    int cr_size;
    int cr_threshold;
} LibWebPContextCommon;

int ff_libwebp_error_to_averror(int err);

av_cold int ff_libwebp_encode_init_common(AVCodecContext *avctx);

int ff_libwebp_get_frame(AVCodecContext *avctx, LibWebPContextCommon *s,
                         const AVFrame *frame, AVFrame **alt_frame_ptr,
                         WebPPicture **pic_ptr);

#define OFFSET(x) offsetof(LibWebPContextCommon, x)
#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
    { "lossless",   "Use lossless mode",       OFFSET(lossless), AV_OPT_TYPE_INT,   { .i64 =  0 },  0, 1,                           VE           },
    { "preset",     "Configuration preset",    OFFSET(preset),   AV_OPT_TYPE_INT,   { .i64 = -1 }, -1, WEBP_PRESET_TEXT,            VE, "preset" },
    { "none",       "do not use a preset",                              0, AV_OPT_TYPE_CONST, { .i64 = -1                  }, 0, 0, VE, "preset" },
    { "default",    "default preset",                                   0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_DEFAULT }, 0, 0, VE, "preset" },
    { "picture",    "digital picture, like portrait, inner shot",       0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_PICTURE }, 0, 0, VE, "preset" },
    { "photo",      "outdoor photograph, with natural lighting",        0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_PHOTO   }, 0, 0, VE, "preset" },
    { "drawing",    "hand or line drawing, with high-contrast details", 0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_DRAWING }, 0, 0, VE, "preset" },
    { "icon",       "small-sized colorful images",                      0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_ICON    }, 0, 0, VE, "preset" },
    { "text",       "text-like",                                        0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_TEXT    }, 0, 0, VE, "preset" },
    { "cr_threshold","Conditional replenishment threshold",     OFFSET(cr_threshold), AV_OPT_TYPE_INT, { .i64 =  0  },  0, INT_MAX, VE           },
    { "cr_size"     ,"Conditional replenishment block size",    OFFSET(cr_size)     , AV_OPT_TYPE_INT, { .i64 =  16 },  0, 256,     VE           },
    { "quality"     ,"Quality",                OFFSET(quality),  AV_OPT_TYPE_FLOAT, { .dbl =  75 }, 0, 100,                         VE           },
    { NULL },
};

static const AVCodecDefault libwebp_defaults[] = {
    { "compression_level",  "4"  },
    { "global_quality",     "-1" },
    { NULL },
};

#endif /* AVCODEC_LIBWEBPENC_COMMON_H */