PeerStreamer

/*

 * DPX (.dpx) image encoder

 * Copyright (c) 2011 Peter Ross <pross@xvid.org>

 *

 * 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 "libavutil/intreadwrite.h"

#include "libavutil/imgutils.h"

#include "avcodec.h"

typedef struct DPXContext {

    AVFrame picture;

    int big_endian;

    int bits_per_component;

    int descriptor;

} DPXContext;

static av_cold int encode_init(AVCodecContext *avctx)

{

    DPXContext *s = avctx->priv_data;

    avctx->coded_frame = &s->picture;

    avctx->coded_frame->pict_type = FF_I_TYPE;

    avctx->coded_frame->key_frame = 1;

    s->big_endian         = 1;

    s->bits_per_component = 8;

    s->descriptor         = 50; /* RGB */

    switch (avctx->pix_fmt) {

    case PIX_FMT_RGB24:

        break;

    case PIX_FMT_RGBA:

        s->descriptor = 51; /* RGBA */

        break;

    case PIX_FMT_RGB48LE:

        s->big_endian = 0;

    case PIX_FMT_RGB48BE:

        s->bits_per_component = avctx->bits_per_raw_sample ? avctx->bits_per_raw_sample : 16;

        break;

    default:

        av_log(avctx, AV_LOG_INFO, "unsupported pixel format\n");

        return -1;

    }

    return 0;

}

#define write16(p, value) \

do { \

    if (s->big_endian) AV_WB16(p, value); \

    else               AV_WL16(p, value); \

} while(0)

#define write32(p, value) \

do { \

    if (s->big_endian) AV_WB32(p, value); \

    else               AV_WL32(p, value); \

} while(0)

static void encode_rgb48_10bit(AVCodecContext *avctx, const AVPicture *pic,

                               uint8_t *dst)

{

    DPXContext *s = avctx->priv_data;

    const uint8_t *src = pic->data[0];

    int x, y;

    for (y = 0; y < avctx->height; y++) {

        for (x = 0; x < avctx->width; x++) {

            int value;

            if ((avctx->pix_fmt & 1)) {

                value = ((AV_RB16(src + 6*x + 4) & 0xFFC0) >> 4)

                      | ((AV_RB16(src + 6*x + 2) & 0xFFC0) << 6)

                      | ((AV_RB16(src + 6*x + 0) & 0xFFC0) << 16);

            } else {

                value = ((AV_RL16(src + 6*x + 4) & 0xFFC0) >> 4)

                      | ((AV_RL16(src + 6*x + 2) & 0xFFC0) << 6)

                      | ((AV_RL16(src + 6*x + 0) & 0xFFC0) << 16);

            }

            write32(dst, value);

            dst += 4;

        }

        src += pic->linesize[0];

    }

}

static int encode_frame(AVCodecContext *avctx, unsigned char *buf,

                        int buf_size, void *data)

{

    DPXContext *s = avctx->priv_data;

    int size;

#define HEADER_SIZE 1664  /* DPX Generic header */

    if (buf_size < HEADER_SIZE)

        return -1;

    memset(buf, 0, HEADER_SIZE);

    /* File information header */

    write32(buf,       MKBETAG('S','D','P','X'));

    write32(buf +   4, HEADER_SIZE);

    memcpy (buf +   8, "V1.0", 4);

    write32(buf +  20, 1); /* new image */

    write32(buf +  24, HEADER_SIZE);

    memcpy (buf + 160, LIBAVCODEC_IDENT, FFMIN(sizeof(LIBAVCODEC_IDENT), 100));

    write32(buf + 660, 0xFFFFFFFF); /* unencrypted */

    /* Image information header */

    write16(buf + 768, 0); /* orientation; left to right, top to bottom */

    write16(buf + 770, 1); /* number of elements */

    write32(buf + 772, avctx->width);

    write32(buf + 776, avctx->height);

    buf[800] = s->descriptor;

    buf[801] = 2; /* linear transfer */

    buf[802] = 2; /* linear colorimetric */

    buf[803] = s->bits_per_component;

    write16(buf + 804, s->bits_per_component == 10 ? 1 : 0); /* packing method */

    /* Image source information header */

    write32(buf + 1628, avctx->sample_aspect_ratio.num);

    write32(buf + 1632, avctx->sample_aspect_ratio.den);

    switch (s->bits_per_component) {

    case 8:

    case 16:

        size = avpicture_layout(data, avctx->pix_fmt,

                                avctx->width, avctx->height,

                                buf + HEADER_SIZE, buf_size - HEADER_SIZE);

        if (size < 0)

            return size;

        break;

    case 10:

        size = avctx->height * avctx->width * 4;

        if (buf_size < HEADER_SIZE + size)

            return -1;

        encode_rgb48_10bit(avctx, data, buf + HEADER_SIZE);

        break;

    default:

        av_log(avctx, AV_LOG_ERROR, "Unsupported bit depth: %d\n", s->bits_per_component);

        return -1;

    }

    size += HEADER_SIZE;

    write32(buf + 16, size); /* file size */

    return size;

}

AVCodec ff_dpx_encoder = {

    .name = "dpx",

    .type = AVMEDIA_TYPE_VIDEO,

    .id   = CODEC_ID_DPX,

    .priv_data_size = sizeof(DPXContext),

    .init   = encode_init,

    .encode = encode_frame,

    .pix_fmts = (const enum PixelFormat[]){

        PIX_FMT_RGB24,

        PIX_FMT_RGBA,

        PIX_FMT_RGB48LE,

        PIX_FMT_RGB48BE,

        PIX_FMT_NONE},

    .long_name = NULL_IF_CONFIG_SMALL("DPX image"),

};