PeerStreamer

/*

 * Raw Video Decoder

 * Copyright (c) 2001 Fabrice Bellard

 *

 * 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

 * Raw Video Decoder

 */

#include "avcodec.h"

#include "imgconvert.h"

#include "raw.h"

#include "libavutil/intreadwrite.h"

#include "libavcore/imgutils.h"

typedef struct RawVideoContext {

    uint32_t palette[AVPALETTE_COUNT];

    unsigned char * buffer;  /* block of memory for holding one frame */

    int             length;  /* number of bytes in buffer */

    int flip;

    AVFrame pic;             ///< AVCodecContext.coded_frame

} RawVideoContext;

static const PixelFormatTag pix_fmt_bps_avi[] = {

    { PIX_FMT_PAL8,    4 },

    { PIX_FMT_PAL8,    8 },

    { PIX_FMT_RGB444, 12 },

    { PIX_FMT_RGB555, 15 },

    { PIX_FMT_RGB555, 16 },

    { PIX_FMT_BGR24,  24 },

    { PIX_FMT_RGB32,  32 },

    { PIX_FMT_NONE, 0 },

};

static const PixelFormatTag pix_fmt_bps_mov[] = {

    { PIX_FMT_MONOWHITE, 1 },

    { PIX_FMT_PAL8,      2 },

    { PIX_FMT_PAL8,      4 },

    { PIX_FMT_PAL8,      8 },

    // FIXME swscale does not support 16 bit in .mov, sample 16bit.mov

    // http://developer.apple.com/documentation/QuickTime/QTFF/QTFFChap3/qtff3.html

    { PIX_FMT_RGB555BE, 16 },

    { PIX_FMT_RGB24,    24 },

    { PIX_FMT_ARGB,     32 },

    { PIX_FMT_NONE, 0 },

};

static enum PixelFormat find_pix_fmt(const PixelFormatTag *tags, unsigned int fourcc)

{

    while (tags->pix_fmt >= 0) {

        if (tags->fourcc == fourcc)

            return tags->pix_fmt;

        tags++;

    }

    return PIX_FMT_YUV420P;

}

static av_cold int raw_init_decoder(AVCodecContext *avctx)

{

    RawVideoContext *context = avctx->priv_data;

    if (avctx->codec_tag == MKTAG('r','a','w',' '))

        avctx->pix_fmt = find_pix_fmt(pix_fmt_bps_mov, avctx->bits_per_coded_sample);

    else if (avctx->codec_tag)

        avctx->pix_fmt = find_pix_fmt(ff_raw_pix_fmt_tags, avctx->codec_tag);

    else if (avctx->pix_fmt == PIX_FMT_NONE && avctx->bits_per_coded_sample)

        avctx->pix_fmt = find_pix_fmt(pix_fmt_bps_avi, avctx->bits_per_coded_sample);

    ff_set_systematic_pal(context->palette, avctx->pix_fmt);

    context->length = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);

    if((avctx->bits_per_coded_sample == 4 || avctx->bits_per_coded_sample == 2) &&

       avctx->pix_fmt==PIX_FMT_PAL8 &&

       (!avctx->codec_tag || avctx->codec_tag == MKTAG('r','a','w',' '))){

        context->buffer = av_malloc(context->length);

        if (!context->buffer)

            return -1;

    }

    context->pic.pict_type = FF_I_TYPE;

    context->pic.key_frame = 1;

    avctx->coded_frame= &context->pic;

    if((avctx->extradata_size >= 9 && !memcmp(avctx->extradata + avctx->extradata_size - 9, "BottomUp", 9)) ||

       avctx->codec_tag == MKTAG( 3 ,  0 ,  0 ,  0 ))

        context->flip=1;

    return 0;

}

static void flip(AVCodecContext *avctx, AVPicture * picture){

    picture->data[0] += picture->linesize[0] * (avctx->height-1);

    picture->linesize[0] *= -1;

}

static int raw_decode(AVCodecContext *avctx,

                            void *data, int *data_size,

                            AVPacket *avpkt)

{

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    RawVideoContext *context = avctx->priv_data;

    AVFrame * frame = (AVFrame *) data;

    AVPicture * picture = (AVPicture *) data;

    frame->interlaced_frame = avctx->coded_frame->interlaced_frame;

    frame->top_field_first = avctx->coded_frame->top_field_first;

    //2bpp and 4bpp raw in avi and mov (yes this is ugly ...)

    if (context->buffer) {

        int i;

        uint8_t *dst = context->buffer;

        buf_size = context->length - 256*4;

        if (avctx->bits_per_coded_sample == 4){

            for(i=0; 2*i+1 < buf_size; i++){

                dst[2*i+0]= buf[i]>>4;

                dst[2*i+1]= buf[i]&15;

            }

        } else

            for(i=0; 4*i+3 < buf_size; i++){

                dst[4*i+0]= buf[i]>>6;

                dst[4*i+1]= buf[i]>>4&3;

                dst[4*i+2]= buf[i]>>2&3;

                dst[4*i+3]= buf[i]   &3;

            }

        buf= dst;

    }

    if(avctx->codec_tag == MKTAG('A', 'V', '1', 'x') ||

       avctx->codec_tag == MKTAG('A', 'V', 'u', 'p'))

        buf += buf_size - context->length;

    if(buf_size < context->length - (avctx->pix_fmt==PIX_FMT_PAL8 ? 256*4 : 0))

        return -1;

    avpicture_fill(picture, buf, avctx->pix_fmt, avctx->width, avctx->height);

    if((avctx->pix_fmt==PIX_FMT_PAL8 && buf_size < context->length) ||

       (avctx->pix_fmt!=PIX_FMT_PAL8 &&

        (av_pix_fmt_descriptors[avctx->pix_fmt].flags & PIX_FMT_PAL))){

        frame->data[1]= context->palette;

    }

    if (avctx->palctrl && avctx->palctrl->palette_changed) {

        memcpy(frame->data[1], avctx->palctrl->palette, AVPALETTE_SIZE);

        avctx->palctrl->palette_changed = 0;

    }

    if(avctx->pix_fmt==PIX_FMT_BGR24 && ((frame->linesize[0]+3)&~3)*avctx->height <= buf_size)

        frame->linesize[0] = (frame->linesize[0]+3)&~3;

    if(context->flip)

        flip(avctx, picture);

    if (   avctx->codec_tag == MKTAG('Y', 'V', '1', '2')

        || avctx->codec_tag == MKTAG('Y', 'V', 'U', '9'))

        FFSWAP(uint8_t *, picture->data[1], picture->data[2]);

    if(avctx->codec_tag == AV_RL32("yuv2") &&

       avctx->pix_fmt   == PIX_FMT_YUYV422) {

        int x, y;

        uint8_t *line = picture->data[0];

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

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

                line[2*x + 1] ^= 0x80;

            line += picture->linesize[0];

        }

    }

    *data_size = sizeof(AVPicture);

    return buf_size;

}

static av_cold int raw_close_decoder(AVCodecContext *avctx)

{

    RawVideoContext *context = avctx->priv_data;

    av_freep(&context->buffer);

    return 0;

}

AVCodec rawvideo_decoder = {

    "rawvideo",

    AVMEDIA_TYPE_VIDEO,

    CODEC_ID_RAWVIDEO,

    sizeof(RawVideoContext),

    raw_init_decoder,

    NULL,

    raw_close_decoder,

    raw_decode,

    .long_name = NULL_IF_CONFIG_SMALL("raw video"),

};