PeerStreamer

/*

 * IFF PBM/ILBM bitmap decoder

 * Copyright (c) 2010 Peter Ross <pross@xvid.org>

 *

 * 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 libavcodec/iff.c

 * IFF PBM/ILBM bitmap decoder

 */

#include "bytestream.h"

#include "avcodec.h"

/**

 * Convert CMAP buffer (stored in extradata) to lavc palette format

 */

int ff_cmap_read_palette(AVCodecContext *avctx, uint32_t *pal)

{

    int count, i;

    if (avctx->bits_per_coded_sample > 8) {

        av_log(avctx, AV_LOG_ERROR, "bit_per_coded_sample > 8 not supported\n");

        return AVERROR_INVALIDDATA;

    }

    count = 1 << avctx->bits_per_coded_sample;

    if (avctx->extradata_size < count * 3) {

        av_log(avctx, AV_LOG_ERROR, "palette data underflow\n");

        return AVERROR_INVALIDDATA;

    }

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

        pal[i] = AV_RB24( avctx->extradata + i*3 );

    }

    return 0;

}

static av_cold int decode_init(AVCodecContext *avctx)

{

    AVFrame *frame = avctx->priv_data;

    avctx->pix_fmt = PIX_FMT_PAL8;

    frame->reference = 1;

    if (avctx->get_buffer(avctx, frame) < 0) {

        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

        return AVERROR_UNKNOWN;

    }

    return ff_cmap_read_palette(avctx, (uint32_t*)frame->data[1]);

}

/**

 * Interleaved memcpy

 */

static void imemcpy(uint8_t *dst, const uint8_t const *buf, int x, int bps, int plane, int length)

{

    int i, b;

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

        int value = buf[i];

        for (b = 0; b < bps; b++) {

            if (value & (1<<b))

                dst[ (x+i)*bps + 7 - b] |= 1<<plane;

       }

    }

}

/**

 * Interleaved memset

 */

static void imemset(uint8_t *dst, int value, int x, int bps, int plane, int length)

{

    int i, b;

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

        for (b = 0; b < bps; b++) {

            if (value & (1<<b))

                dst[ (x+i)*bps + 7 - b] |= 1<<plane;

       }

    }

}

static int decode_frame_ilbm(AVCodecContext *avctx,

                            void *data, int *data_size,

                            AVPacket *avpkt)

{

    AVFrame *frame = avctx->priv_data;

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    int planewidth = avctx->width / avctx->bits_per_coded_sample;

    int y, plane;

    if (avctx->reget_buffer(avctx, frame) < 0){

        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

        return -1;

    }

    if (buf_size < avctx->width * avctx->height) {

        av_log(avctx, AV_LOG_ERROR, "buffer underflow\n");

        return -1;

    }

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

        uint8_t *row = &frame->data[0][ y*frame->linesize[0] ];

        memset(row, 0, avctx->width);

        for (plane = 0; plane < avctx->bits_per_coded_sample; plane++) {

            imemcpy(row, buf, 0, avctx->bits_per_coded_sample, plane, planewidth);

            buf += planewidth;

        }

    }

    *data_size = sizeof(AVFrame);

    *(AVFrame*)data = *frame;

    return buf_size;

}

static int decode_frame_byterun1(AVCodecContext *avctx,

                            void *data, int *data_size,

                            AVPacket *avpkt)

{

    AVFrame *frame = avctx->priv_data;

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    const uint8_t *buf_end = buf+buf_size;

    int planewidth = avctx->width / avctx->bits_per_coded_sample;

    int y, plane, x;

    if (avctx->reget_buffer(avctx, frame) < 0){

        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

        return -1;

    }

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

        uint8_t *row = &frame->data[0][ y*frame->linesize[0] ];

        if (avctx->codec_tag == MKTAG('I','L','B','M')) { //interleaved

            memset(row, 0, avctx->width);

            for (plane = 0; plane < avctx->bits_per_coded_sample; plane++) {

                for(x = 0; x < planewidth && buf < buf_end; ) {

                    int8_t value = *buf++;

                    int length;

                    if (value >= 0) {

                        length = value + 1;

                        imemcpy(row, buf, x, avctx->bits_per_coded_sample, plane, FFMIN3(length, buf_end - buf, planewidth - x));

                        buf += length;

                    } else if (value > -128) {

                        length = -value + 1;

                        imemset(row, *buf++, x, avctx->bits_per_coded_sample, plane, FFMIN(length, planewidth - x));

                    } else { //noop

                        continue;

                    }

                    x += length;

                }

            }

        } else {

            for(x = 0; x < avctx->width && buf < buf_end; ) {

                int8_t value = *buf++;

                int length;

                if (value >= 0) {

                    length = value + 1;

                    memcpy(row + x, buf, FFMIN3(length, buf_end - buf, avctx->width - x));

                    buf += length;

                } else if (value > -128) {

                    length = -value + 1;

                    memset(row + x, *buf++, FFMIN(length, avctx->width - x));

                } else { //noop

                    continue;

                }

                x += length;

            }

        }

    }

    *data_size = sizeof(AVFrame);

    *(AVFrame*)data = *frame;

    return buf_size;

}

static av_cold int decode_end(AVCodecContext *avctx)

{

    AVFrame *frame = avctx->priv_data;

    if (frame->data[0])

        avctx->release_buffer(avctx, frame);

    return 0;

}

AVCodec iff_ilbm_decoder = {

    "iff_ilbm",

    CODEC_TYPE_VIDEO,

    CODEC_ID_IFF_ILBM,

    sizeof(AVFrame),

    decode_init,

    NULL,

    decode_end,

    decode_frame_ilbm,

    CODEC_CAP_DR1,

    .long_name = NULL_IF_CONFIG_SMALL("IFF ILBM"),

};

AVCodec iff_byterun1_decoder = {

    "iff_byterun1",

    CODEC_TYPE_VIDEO,

    CODEC_ID_IFF_BYTERUN1,

    sizeof(AVFrame),

    decode_init,

    NULL,

    decode_end,

    decode_frame_byterun1,

    CODEC_CAP_DR1,

    .long_name = NULL_IF_CONFIG_SMALL("IFF ByteRun1"),

};