/*

 * lossless JPEG encoder

 * Copyright (c) 2000, 2001 Fabrice Bellard

 * Copyright (c) 2003 Alex Beregszaszi

 * Copyright (c) 2003-2004 Michael Niedermayer

 *

 * Support for external huffman table, various fixes (AVID workaround),

 * aspecting, new decode_frame mechanism and apple mjpeg-b support

 *                                  by Alex Beregszaszi

 *

 * 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

 * lossless JPEG encoder.

 */

#include "libavutil/frame.h"

#include "libavutil/mem.h"

#include "libavutil/opt.h"

#include "avcodec.h"

#include "codec_internal.h"

#include "encode.h"

#include "jpegtables.h"

#include "mjpegenc_common.h"

#include "mjpeg.h"

typedef struct LJpegEncContext {

    AVClass *class;

    int vsample[4];

    int hsample[4];

    uint16_t huff_code_dc_luminance[12];

    uint16_t huff_code_dc_chrominance[12];

    uint8_t  huff_size_dc_luminance[12];

    uint8_t  huff_size_dc_chrominance[12];

    uint16_t (*scratch)[4];

    int pred;

} LJpegEncContext;

static int ljpeg_encode_bgr(AVCodecContext *avctx, PutBitContext *pb,

                            const AVFrame *frame)

{

    LJpegEncContext *s    = avctx->priv_data;

    const int width       = frame->width;

    const int height      = frame->height;

    const int linesize    = frame->linesize[0];

    uint16_t (*buffer)[4] = s->scratch;

    int left[4], top[4], topleft[4];

    int x, y, i;

    for (i = 0; i < 4; i++)

        buffer[0][i] = 1 << (9 - 1);

    for (y = 0; y < height; y++) {

        const int modified_predictor = y ? s->pred : 1;

        const uint8_t *ptr = frame->data[0] + (linesize * y);

        if (put_bytes_left(pb, 0) < width * 4 * 4) {

            av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n");

            return -1;

        }

        for (i = 0; i < 4; i++)

            top[i]= left[i]= topleft[i]= buffer[0][i];

        for (x = 0; x < width; x++) {

            if(avctx->pix_fmt == AV_PIX_FMT_BGR24){

                buffer[x][1] =  ptr[3 * x + 0] -     ptr[3 * x + 1] + 0x100;

                buffer[x][2] =  ptr[3 * x + 2] -     ptr[3 * x + 1] + 0x100;

                buffer[x][0] = (ptr[3 * x + 0] + 2 * ptr[3 * x + 1] + ptr[3 * x + 2]) >> 2;

            }else{

                buffer[x][1] =  ptr[4 * x + 0] -     ptr[4 * x + 1] + 0x100;

                buffer[x][2] =  ptr[4 * x + 2] -     ptr[4 * x + 1] + 0x100;

                buffer[x][0] = (ptr[4 * x + 0] + 2 * ptr[4 * x + 1] + ptr[4 * x + 2]) >> 2;

                if (avctx->pix_fmt == AV_PIX_FMT_BGRA)

                    buffer[x][3] =  ptr[4 * x + 3];

            }

            for (i = 0; i < 3 + (avctx->pix_fmt == AV_PIX_FMT_BGRA); i++) {

                int pred, diff;

                PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);

                topleft[i] = top[i];

                top[i]     = buffer[x+1][i];

                left[i]    = buffer[x][i];

                diff       = ((left[i] - pred + 0x100) & 0x1FF) - 0x100;

                if (i == 0 || i == 3)

                    ff_mjpeg_encode_dc(pb, diff, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly

                else

                    ff_mjpeg_encode_dc(pb, diff, s->huff_size_dc_chrominance, s->huff_code_dc_chrominance);

            }

        }

    }

    return 0;

}

static inline void ljpeg_encode_yuv_mb(LJpegEncContext *s, PutBitContext *pb,

                                       const AVFrame *frame, int predictor,

                                       int mb_x, int mb_y)

{

    int i;

    if (mb_x == 0 || mb_y == 0) {

        for (i = 0; i < 3; i++) {

            const uint8_t *ptr;

            int x, y, h, v, linesize;

            h = s->hsample[i];

            v = s->vsample[i];

            linesize = frame->linesize[i];

            for (y = 0; y < v; y++) {

                for (x = 0; x < h; x++) {

                    int pred;

                    ptr = frame->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap

                    if (y == 0 && mb_y == 0) {

                        if (x == 0 && mb_x == 0)

                            pred = 128;

                        else

                            pred = ptr[-1];

                    } else {

                        if (x == 0 && mb_x == 0) {

                            pred = ptr[-linesize];

                        } else {

                            PREDICT(pred, ptr[-linesize - 1], ptr[-linesize],

                                    ptr[-1], predictor);

                        }

                    }

                    if (i == 0)

                        ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly

                    else

                        ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_chrominance, s->huff_code_dc_chrominance);

                }

            }

        }

    } else {

        for (i = 0; i < 3; i++) {

            const uint8_t *ptr;

            int x, y, h, v, linesize;

            h = s->hsample[i];

            v = s->vsample[i];

            linesize = frame->linesize[i];

            for (y = 0; y < v; y++) {

                for (x = 0; x < h; x++) {

                    int pred;

                    ptr = frame->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap

                    PREDICT(pred, ptr[-linesize - 1], ptr[-linesize], ptr[-1], predictor);

                    if (i == 0)

                        ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly

                    else

                        ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_chrominance, s->huff_code_dc_chrominance);

                }

            }

        }

    }

}

static int ljpeg_encode_yuv(AVCodecContext *avctx, PutBitContext *pb,

                            const AVFrame *frame)

{

    LJpegEncContext *s  = avctx->priv_data;

    const int mb_width  = (avctx->width  + s->hsample[0] - 1) / s->hsample[0];

    const int mb_height = (avctx->height + s->vsample[0] - 1) / s->vsample[0];

    int mb_x, mb_y;

    for (mb_y = 0; mb_y < mb_height; mb_y++) {

        if (put_bytes_left(pb, 0) <

            mb_width * 4 * 3 * s->hsample[0] * s->vsample[0]) {

            av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n");

            return -1;

        }

        for (mb_x = 0; mb_x < mb_width; mb_x++)

            ljpeg_encode_yuv_mb(s, pb, frame, s->pred, mb_x, mb_y);

    }

    return 0;

}

static int ljpeg_encode_frame(AVCodecContext *avctx, AVPacket *pkt,

                              const AVFrame *pict, int *got_packet)

{

    LJpegEncContext *s = avctx->priv_data;

    PutBitContext pb;

    const int width  = avctx->width;

    const int height = avctx->height;

    const int mb_width  = (width  + s->hsample[0] - 1) / s->hsample[0];

    const int mb_height = (height + s->vsample[0] - 1) / s->vsample[0];

    size_t max_pkt_size = FF_INPUT_BUFFER_MIN_SIZE;

    int ret, header_bits;

    if(    avctx->pix_fmt == AV_PIX_FMT_BGR0

        || avctx->pix_fmt == AV_PIX_FMT_BGR24)

        max_pkt_size += width * height * 3 * 4;

    else if(avctx->pix_fmt == AV_PIX_FMT_BGRA)

        max_pkt_size += width * height * 4 * 4;

    else {

        max_pkt_size += mb_width * mb_height * 3 * 4

                        * s->hsample[0] * s->vsample[0];

    }

    if ((ret = ff_mjpeg_add_icc_profile_size(avctx, pict, &max_pkt_size)) < 0)

        return ret;

    if ((ret = ff_alloc_packet(avctx, pkt, max_pkt_size)) < 0)

        return ret;

    init_put_bits(&pb, pkt->data, pkt->size);

    ff_mjpeg_encode_picture_header(avctx, &pb, pict, NULL, NULL,

                                   s->pred, NULL, NULL, 0);

    header_bits = put_bits_count(&pb);

    if(    avctx->pix_fmt == AV_PIX_FMT_BGR0

        || avctx->pix_fmt == AV_PIX_FMT_BGRA

        || avctx->pix_fmt == AV_PIX_FMT_BGR24)

        ret = ljpeg_encode_bgr(avctx, &pb, pict);

    else

        ret = ljpeg_encode_yuv(avctx, &pb, pict);

    if (ret < 0)

        return ret;

    ff_mjpeg_escape_FF(&pb, header_bits >> 3);

    ff_mjpeg_encode_picture_trailer(&pb, header_bits);

    flush_put_bits(&pb);

    pkt->size   = put_bytes_output(&pb);

    *got_packet = 1;

    return 0;

}

static av_cold int ljpeg_encode_close(AVCodecContext *avctx)

{

    LJpegEncContext *s = avctx->priv_data;

    av_freep(&s->scratch);

    return 0;

}

static av_cold int ljpeg_encode_init(AVCodecContext *avctx)

{

    int ret = ff_mjpeg_encode_check_pix_fmt(avctx);

    LJpegEncContext *s = avctx->priv_data;

    if (ret < 0)

        return ret;

    s->scratch = av_malloc_array(avctx->width + 1, sizeof(*s->scratch));

    if (!s->scratch)

        return AVERROR(ENOMEM);

    ff_mjpeg_init_hvsample(avctx, s->hsample, s->vsample);

    ff_mjpeg_build_huffman_codes(s->huff_size_dc_luminance,

                                 s->huff_code_dc_luminance,

                                 ff_mjpeg_bits_dc_luminance,

                                 ff_mjpeg_val_dc);

    ff_mjpeg_build_huffman_codes(s->huff_size_dc_chrominance,

                                 s->huff_code_dc_chrominance,

                                 ff_mjpeg_bits_dc_chrominance,

                                 ff_mjpeg_val_dc);

    return 0;

}

#define OFFSET(x) offsetof(LJpegEncContext, x)

#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM

static const AVOption options[] = {

{ "pred", "Prediction method", OFFSET(pred), AV_OPT_TYPE_INT, { .i64 = 1 }, 1, 3, VE, .unit = "pred" },

    { "left",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN, INT_MAX, VE, .unit = "pred" },

    { "plane",  NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 2 }, INT_MIN, INT_MAX, VE, .unit = "pred" },

    { "median", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 3 }, INT_MIN, INT_MAX, VE, .unit = "pred" },

    { NULL},

};

static const AVClass ljpeg_class = {

    .class_name = "ljpeg",

    .item_name  = av_default_item_name,

    .option     = options,

    .version    = LIBAVUTIL_VERSION_INT,

};

const FFCodec ff_ljpeg_encoder = {

    .p.name         = "ljpeg",

    CODEC_LONG_NAME("Lossless JPEG"),

    .p.type         = AVMEDIA_TYPE_VIDEO,

    .p.id           = AV_CODEC_ID_LJPEG,

    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS |

                      AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,

    .priv_data_size = sizeof(LJpegEncContext),

    .p.priv_class   = &ljpeg_class,

    .init           = ljpeg_encode_init,

    FF_CODEC_ENCODE_CB(ljpeg_encode_frame),

    .close          = ljpeg_encode_close,

    CODEC_PIXFMTS(AV_PIX_FMT_BGR24,    AV_PIX_FMT_BGRA,     AV_PIX_FMT_BGR0,

                  AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,

                  AV_PIX_FMT_YUV420P,  AV_PIX_FMT_YUV444P,  AV_PIX_FMT_YUV422P),

    .color_ranges   = AVCOL_RANGE_MPEG | AVCOL_RANGE_JPEG,

};