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"

#include "get_bits.h"

typedef struct {

    AVFrame frame;

    int planesize;

    uint8_t * planebuf;

} IffContext;

/**

 * 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] = 0xFF000000 | AV_RB24( avctx->extradata + i*3 );

    }

    return 0;

}

static av_cold int decode_init(AVCodecContext *avctx)

{

    IffContext *s = avctx->priv_data;

    if (avctx->bits_per_coded_sample <= 8) {

        avctx->pix_fmt = PIX_FMT_PAL8;

    } else if (avctx->bits_per_coded_sample <= 32) {

        avctx->pix_fmt = PIX_FMT_BGR32;

    } else {

        return AVERROR_INVALIDDATA;

    }

    s->planesize = avctx->width / 8;

    s->planebuf = av_malloc(s->planesize + FF_INPUT_BUFFER_PADDING_SIZE);

    if (!s->planebuf)

        return AVERROR(ENOMEM);

    s->frame.reference = 1;

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

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

        return AVERROR_UNKNOWN;

    }

    return avctx->bits_per_coded_sample <= 8 ?

       ff_cmap_read_palette(avctx, (uint32_t*)s->frame.data[1]) : 0;

}

/**

 * Decode interleaved plane buffer

 * @param dst Destination buffer

 * @param buf Source buffer

 * @param buf_size

 * @param bps bits_per_coded_sample

 * @param plane plane number to decode as

 */

#define DECLARE_DECODEPLANE(suffix, type) \

static void decodeplane##suffix(void *dst, const uint8_t const *buf, int buf_size, int bps, int plane) \

{ \

    GetBitContext gb; \

    int i, b; \

    init_get_bits(&gb, buf, buf_size * 8); \

    for(i = 0; i < (buf_size * 8 + bps - 1) / bps; i++) { \

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

            ((type *)dst)[ i*bps + b ] |= get_bits1(&gb) << plane; \

        } \

    } \

}

DECLARE_DECODEPLANE(8, uint8_t)

DECLARE_DECODEPLANE(32, uint32_t)

static int decode_frame_ilbm(AVCodecContext *avctx,

                            void *data, int *data_size,

                            AVPacket *avpkt)

{

    IffContext *s = avctx->priv_data;

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    int y, plane;

    if (avctx->reget_buffer(avctx, &s->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 = &s->frame.data[0][ y*s->frame.linesize[0] ];

        memset(row, 0, avctx->pix_fmt == PIX_FMT_PAL8 ? avctx->width : (avctx->width * 4));

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

            if (avctx->pix_fmt == PIX_FMT_PAL8) {

                decodeplane8(row, buf, s->planesize, avctx->bits_per_coded_sample, plane);

            } else { // PIX_FMT_BGR32

                decodeplane32(row, buf, s->planesize, avctx->bits_per_coded_sample, plane);

            }

            buf += s->planesize;

        }

    }

    *data_size = sizeof(AVFrame);

    *(AVFrame*)data = s->frame;

    return buf_size;

}

static int decode_frame_byterun1(AVCodecContext *avctx,

                            void *data, int *data_size,

                            AVPacket *avpkt)

{

    IffContext *s = avctx->priv_data;

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    const uint8_t *buf_end = buf+buf_size;

    int y, plane, x;

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

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

        return -1;

    }

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

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

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

            memset(row, 0, avctx->pix_fmt == PIX_FMT_PAL8 ? avctx->width : (avctx->width * 4));

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

                for(x = 0; x < s->planesize && buf < buf_end; ) {

                    int8_t value = *buf++;

                    int length;

                    if (value >= 0) {

                        length = value + 1;

                        memcpy(s->planebuf + x, buf, FFMIN3(length, s->planesize - x, buf_end - buf));

                        buf += length;

                    } else if (value > -128) {

                        length = -value + 1;

                        memset(s->planebuf + x, *buf++, FFMIN(length, s->planesize - x));

                    } else { //noop

                        continue;

                    }

                    x += length;

                }

                if (avctx->pix_fmt == PIX_FMT_PAL8) {

                    decodeplane8(row, s->planebuf, s->planesize, avctx->bits_per_coded_sample, plane);

                } else { //PIX_FMT_BGR32

                    decodeplane32(row, s->planebuf, s->planesize, avctx->bits_per_coded_sample, plane);

                }

            }

        } 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 = s->frame;

    return buf_size;

}

static av_cold int decode_end(AVCodecContext *avctx)

{

    IffContext *s = avctx->priv_data;

    if (s->frame.data[0])

        avctx->release_buffer(avctx, &s->frame);

    av_freep(&s->planebuf);

    return 0;

}

AVCodec iff_ilbm_decoder = {

    "iff_ilbm",

    CODEC_TYPE_VIDEO,

    CODEC_ID_IFF_ILBM,

    sizeof(IffContext),

    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(IffContext),

    decode_init,

    NULL,

    decode_end,

    decode_frame_byterun1,

    CODEC_CAP_DR1,

    .long_name = NULL_IF_CONFIG_SMALL("IFF ByteRun1"),

};