PeerStreamer

/*

 * Zip Motion Blocks Video (ZMBV) decoder

 * Copyright (c) 2006 Konstantin Shishkov

 *

 * 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

 * Zip Motion Blocks Video decoder

 */

#include <stdio.h>

#include <stdlib.h>

#include "libavutil/intreadwrite.h"

#include "avcodec.h"

#include <zlib.h>

#define ZMBV_KEYFRAME 1

#define ZMBV_DELTAPAL 2

enum ZmbvFormat {

    ZMBV_FMT_NONE  = 0,

    ZMBV_FMT_1BPP  = 1,

    ZMBV_FMT_2BPP  = 2,

    ZMBV_FMT_4BPP  = 3,

    ZMBV_FMT_8BPP  = 4,

    ZMBV_FMT_15BPP = 5,

    ZMBV_FMT_16BPP = 6,

    ZMBV_FMT_24BPP = 7,

    ZMBV_FMT_32BPP = 8

};

/*

 * Decoder context

 */

typedef struct ZmbvContext {

    AVCodecContext *avctx;

    AVFrame pic;

    int bpp;

    unsigned int decomp_size;

    uint8_t* decomp_buf;

    uint8_t pal[768];

    uint8_t *prev, *cur;

    int width, height;

    int fmt;

    int comp;

    int flags;

    int bw, bh, bx, by;

    int decomp_len;

    z_stream zstream;

    int (*decode_intra)(struct ZmbvContext *c);

    int (*decode_xor)(struct ZmbvContext *c);

} ZmbvContext;

/**

 * Decode XOR'ed frame - 8bpp version

 */

static int zmbv_decode_xor_8(ZmbvContext *c)

{

    uint8_t *src = c->decomp_buf;

    uint8_t *output, *prev;

    int8_t *mvec;

    int x, y;

    int d, dx, dy, bw2, bh2;

    int block;

    int i, j;

    int mx, my;

    output = c->cur;

    prev = c->prev;

    if(c->flags & ZMBV_DELTAPAL){

        for(i = 0; i < 768; i++)

            c->pal[i] ^= *src++;

    }

    mvec = (int8_t*)src;

    src += ((c->bx * c->by * 2 + 3) & ~3);

    block = 0;

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

        bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);

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

            uint8_t *out, *tprev;

            d = mvec[block] & 1;

            dx = mvec[block] >> 1;

            dy = mvec[block + 1] >> 1;

            block += 2;

            bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);

            /* copy block - motion vectors out of bounds are used to zero blocks */

            out = output + x;

            tprev = prev + x + dx + dy * c->width;

            mx = x + dx;

            my = y + dy;

            for(j = 0; j < bh2; j++){

                if((my + j < 0) || (my + j >= c->height)) {

                    memset(out, 0, bw2);

                } else {

                    for(i = 0; i < bw2; i++){

                        if((mx + i < 0) || (mx + i >= c->width))

                            out[i] = 0;

                        else

                            out[i] = tprev[i];

                    }

                }

                out += c->width;

                tprev += c->width;

            }

            if(d) { /* apply XOR'ed difference */

                out = output + x;

                for(j = 0; j < bh2; j++){

                    for(i = 0; i < bw2; i++)

                        out[i] ^= *src++;

                    out += c->width;

                }

            }

        }

        output += c->width * c->bh;

        prev += c->width * c->bh;

    }

    if(src - c->decomp_buf != c->decomp_len)

        av_log(c->avctx, AV_LOG_ERROR, "Used %ti of %i bytes\n", src-c->decomp_buf, c->decomp_len);

    return 0;

}

/**

 * Decode XOR'ed frame - 15bpp and 16bpp version

 */

static int zmbv_decode_xor_16(ZmbvContext *c)

{

    uint8_t *src = c->decomp_buf;

    uint16_t *output, *prev;

    int8_t *mvec;

    int x, y;

    int d, dx, dy, bw2, bh2;

    int block;

    int i, j;

    int mx, my;

    output = (uint16_t*)c->cur;

    prev = (uint16_t*)c->prev;

    mvec = (int8_t*)src;

    src += ((c->bx * c->by * 2 + 3) & ~3);

    block = 0;

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

        bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);

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

            uint16_t *out, *tprev;

            d = mvec[block] & 1;

            dx = mvec[block] >> 1;

            dy = mvec[block + 1] >> 1;

            block += 2;

            bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);

            /* copy block - motion vectors out of bounds are used to zero blocks */

            out = output + x;

            tprev = prev + x + dx + dy * c->width;

            mx = x + dx;

            my = y + dy;

            for(j = 0; j < bh2; j++){

                if((my + j < 0) || (my + j >= c->height)) {

                    memset(out, 0, bw2 * 2);

                } else {

                    for(i = 0; i < bw2; i++){

                        if((mx + i < 0) || (mx + i >= c->width))

                            out[i] = 0;

                        else

                            out[i] = tprev[i];

                    }

                }

                out += c->width;

                tprev += c->width;

            }

            if(d) { /* apply XOR'ed difference */

                out = output + x;

                for(j = 0; j < bh2; j++){

                    for(i = 0; i < bw2; i++) {

                        out[i] ^= *((uint16_t*)src);

                        src += 2;

                    }

                    out += c->width;

                }

            }

        }

        output += c->width * c->bh;

        prev += c->width * c->bh;

    }

    if(src - c->decomp_buf != c->decomp_len)

        av_log(c->avctx, AV_LOG_ERROR, "Used %ti of %i bytes\n", src-c->decomp_buf, c->decomp_len);

    return 0;

}

#ifdef ZMBV_ENABLE_24BPP

/**

 * Decode XOR'ed frame - 24bpp version

 */

static int zmbv_decode_xor_24(ZmbvContext *c)

{

    uint8_t *src = c->decomp_buf;

    uint8_t *output, *prev;

    int8_t *mvec;

    int x, y;

    int d, dx, dy, bw2, bh2;

    int block;

    int i, j;

    int mx, my;

    int stride;

    output = c->cur;

    prev = c->prev;

    stride = c->width * 3;

    mvec = (int8_t*)src;

    src += ((c->bx * c->by * 2 + 3) & ~3);

    block = 0;

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

        bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);

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

            uint8_t *out, *tprev;

            d = mvec[block] & 1;

            dx = mvec[block] >> 1;

            dy = mvec[block + 1] >> 1;

            block += 2;

            bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);

            /* copy block - motion vectors out of bounds are used to zero blocks */

            out = output + x * 3;

            tprev = prev + (x + dx) * 3 + dy * stride;

            mx = x + dx;

            my = y + dy;

            for(j = 0; j < bh2; j++){

                if((my + j < 0) || (my + j >= c->height)) {

                    memset(out, 0, bw2 * 3);

                } else {

                    for(i = 0; i < bw2; i++){

                        if((mx + i < 0) || (mx + i >= c->width)) {

                            out[i * 3 + 0] = 0;

                            out[i * 3 + 1] = 0;

                            out[i * 3 + 2] = 0;

                        } else {

                            out[i * 3 + 0] = tprev[i * 3 + 0];

                            out[i * 3 + 1] = tprev[i * 3 + 1];

                            out[i * 3 + 2] = tprev[i * 3 + 2];

                        }

                    }

                }

                out += stride;

                tprev += stride;

            }

            if(d) { /* apply XOR'ed difference */

                out = output + x * 3;

                for(j = 0; j < bh2; j++){

                    for(i = 0; i < bw2; i++) {

                        out[i * 3 + 0] ^= *src++;

                        out[i * 3 + 1] ^= *src++;

                        out[i * 3 + 2] ^= *src++;

                    }

                    out += stride;

                }

            }

        }

        output += stride * c->bh;

        prev += stride * c->bh;

    }

    if(src - c->decomp_buf != c->decomp_len)

        av_log(c->avctx, AV_LOG_ERROR, "Used %i of %i bytes\n", src-c->decomp_buf, c->decomp_len);

    return 0;

}

#endif //ZMBV_ENABLE_24BPP

/**

 * Decode XOR'ed frame - 32bpp version

 */

static int zmbv_decode_xor_32(ZmbvContext *c)

{

    uint8_t *src = c->decomp_buf;

    uint32_t *output, *prev;

    int8_t *mvec;

    int x, y;

    int d, dx, dy, bw2, bh2;

    int block;

    int i, j;

    int mx, my;

    output = (uint32_t*)c->cur;

    prev = (uint32_t*)c->prev;

    mvec = (int8_t*)src;

    src += ((c->bx * c->by * 2 + 3) & ~3);

    block = 0;

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

        bh2 = ((c->height - y) > c->bh) ? c->bh : (c->height - y);

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

            uint32_t *out, *tprev;

            d = mvec[block] & 1;

            dx = mvec[block] >> 1;

            dy = mvec[block + 1] >> 1;

            block += 2;

            bw2 = ((c->width - x) > c->bw) ? c->bw : (c->width - x);

            /* copy block - motion vectors out of bounds are used to zero blocks */

            out = output + x;

            tprev = prev + x + dx + dy * c->width;

            mx = x + dx;

            my = y + dy;

            for(j = 0; j < bh2; j++){

                if((my + j < 0) || (my + j >= c->height)) {

                    memset(out, 0, bw2 * 4);

                } else {

                    for(i = 0; i < bw2; i++){

                        if((mx + i < 0) || (mx + i >= c->width))

                            out[i] = 0;

                        else

                            out[i] = tprev[i];

                    }

                }

                out += c->width;

                tprev += c->width;

            }

            if(d) { /* apply XOR'ed difference */

                out = output + x;

                for(j = 0; j < bh2; j++){

                    for(i = 0; i < bw2; i++) {

                        out[i] ^= *((uint32_t*)src);

                        src += 4;

                    }

                    out += c->width;

                }

            }

        }

        output += c->width * c->bh;

        prev += c->width * c->bh;

    }

    if(src - c->decomp_buf != c->decomp_len)

        av_log(c->avctx, AV_LOG_ERROR, "Used %ti of %i bytes\n", src-c->decomp_buf, c->decomp_len);

    return 0;

}

/**

 * Decode intraframe

 */

static int zmbv_decode_intra(ZmbvContext *c)

{

    uint8_t *src = c->decomp_buf;

    /* make the palette available on the way out */

    if (c->fmt == ZMBV_FMT_8BPP) {

        memcpy(c->pal, src, 768);

        src += 768;

    }

    memcpy(c->cur, src, c->width * c->height * (c->bpp / 8));

    return 0;

}

static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)

{

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    ZmbvContext * const c = avctx->priv_data;

    int zret = Z_OK; // Zlib return code

    int len = buf_size;

    int hi_ver, lo_ver;

    if(c->pic.data[0])

            avctx->release_buffer(avctx, &c->pic);

    c->pic.reference = 1;

    c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;

    if(avctx->get_buffer(avctx, &c->pic) < 0){

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

        return -1;

    }

    /* parse header */

    c->flags = buf[0];

    buf++; len--;

    if(c->flags & ZMBV_KEYFRAME) {

        hi_ver = buf[0];

        lo_ver = buf[1];

        c->comp = buf[2];

        c->fmt = buf[3];

        c->bw = buf[4];

        c->bh = buf[5];

        buf += 6;

        len -= 6;

        av_log(avctx, AV_LOG_DEBUG, "Flags=%X ver=%i.%i comp=%i fmt=%i blk=%ix%i\n",c->flags,hi_ver,lo_ver,c->comp,c->fmt,c->bw,c->bh);

        if(hi_ver != 0 || lo_ver != 1) {

            av_log(avctx, AV_LOG_ERROR, "Unsupported version %i.%i\n", hi_ver, lo_ver);

            return -1;

        }

        if(c->bw == 0 || c->bh == 0) {

            av_log(avctx, AV_LOG_ERROR, "Unsupported block size %ix%i\n", c->bw, c->bh);

            return -1;

        }

        if(c->comp != 0 && c->comp != 1) {

            av_log(avctx, AV_LOG_ERROR, "Unsupported compression type %i\n", c->comp);

            return -1;

        }

        switch(c->fmt) {

        case ZMBV_FMT_8BPP:

            c->bpp = 8;

            c->decode_intra = zmbv_decode_intra;

            c->decode_xor = zmbv_decode_xor_8;

            break;

        case ZMBV_FMT_15BPP:

        case ZMBV_FMT_16BPP:

            c->bpp = 16;

            c->decode_intra = zmbv_decode_intra;

            c->decode_xor = zmbv_decode_xor_16;

            break;

#ifdef ZMBV_ENABLE_24BPP

        case ZMBV_FMT_24BPP:

            c->bpp = 24;

            c->decode_intra = zmbv_decode_intra;

            c->decode_xor = zmbv_decode_xor_24;

            break;

#endif //ZMBV_ENABLE_24BPP

        case ZMBV_FMT_32BPP:

            c->bpp = 32;

            c->decode_intra = zmbv_decode_intra;

            c->decode_xor = zmbv_decode_xor_32;

            break;

        default:

            c->decode_intra = NULL;

            c->decode_xor = NULL;

            av_log(avctx, AV_LOG_ERROR, "Unsupported (for now) format %i\n", c->fmt);

            return -1;

        }

        zret = inflateReset(&c->zstream);

        if (zret != Z_OK) {

            av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);

            return -1;

        }

        c->cur = av_realloc(c->cur, avctx->width * avctx->height * (c->bpp / 8));

        c->prev = av_realloc(c->prev, avctx->width * avctx->height * (c->bpp / 8));

        c->bx = (c->width + c->bw - 1) / c->bw;

        c->by = (c->height+ c->bh - 1) / c->bh;

    }

    if(c->decode_intra == NULL) {

        av_log(avctx, AV_LOG_ERROR, "Error! Got no format or no keyframe!\n");

        return -1;

    }

    if(c->comp == 0) { //Uncompressed data

        memcpy(c->decomp_buf, buf, len);

        c->decomp_size = 1;

    } else { // ZLIB-compressed data

        c->zstream.total_in = c->zstream.total_out = 0;

        c->zstream.next_in = buf;

        c->zstream.avail_in = len;

        c->zstream.next_out = c->decomp_buf;

        c->zstream.avail_out = c->decomp_size;

        inflate(&c->zstream, Z_FINISH);

        c->decomp_len = c->zstream.total_out;

    }

    if(c->flags & ZMBV_KEYFRAME) {

        c->pic.key_frame = 1;

        c->pic.pict_type = AV_PICTURE_TYPE_I;

        c->decode_intra(c);

    } else {

        c->pic.key_frame = 0;

        c->pic.pict_type = AV_PICTURE_TYPE_P;

        if(c->decomp_len)

            c->decode_xor(c);

    }

    /* update frames */

    {

        uint8_t *out, *src;

        int i, j;

        out = c->pic.data[0];

        src = c->cur;

        switch(c->fmt) {

        case ZMBV_FMT_8BPP:

            for(j = 0; j < c->height; j++) {

                for(i = 0; i < c->width; i++) {

                    out[i * 3 + 0] = c->pal[(*src) * 3 + 0];

                    out[i * 3 + 1] = c->pal[(*src) * 3 + 1];

                    out[i * 3 + 2] = c->pal[(*src) * 3 + 2];

                    src++;

                }

                out += c->pic.linesize[0];

            }

            break;

        case ZMBV_FMT_15BPP:

            for(j = 0; j < c->height; j++) {

                for(i = 0; i < c->width; i++) {

                    uint16_t tmp = AV_RL16(src);

                    src += 2;

                    out[i * 3 + 0] = (tmp & 0x7C00) >> 7;

                    out[i * 3 + 1] = (tmp & 0x03E0) >> 2;

                    out[i * 3 + 2] = (tmp & 0x001F) << 3;

                }

                out += c->pic.linesize[0];

            }

            break;

        case ZMBV_FMT_16BPP:

            for(j = 0; j < c->height; j++) {

                for(i = 0; i < c->width; i++) {

                    uint16_t tmp = AV_RL16(src);

                    src += 2;

                    out[i * 3 + 0] = (tmp & 0xF800) >> 8;

                    out[i * 3 + 1] = (tmp & 0x07E0) >> 3;

                    out[i * 3 + 2] = (tmp & 0x001F) << 3;

                }

                out += c->pic.linesize[0];

            }

            break;

#ifdef ZMBV_ENABLE_24BPP

        case ZMBV_FMT_24BPP:

            for(j = 0; j < c->height; j++) {

                memcpy(out, src, c->width * 3);

                src += c->width * 3;

                out += c->pic.linesize[0];

            }

            break;

#endif //ZMBV_ENABLE_24BPP

        case ZMBV_FMT_32BPP:

            for(j = 0; j < c->height; j++) {

                for(i = 0; i < c->width; i++) {

                    uint32_t tmp = AV_RL32(src);

                    src += 4;

                    AV_WB24(out+(i*3), tmp);

                }

                out += c->pic.linesize[0];

            }

            break;

        default:

            av_log(avctx, AV_LOG_ERROR, "Cannot handle format %i\n", c->fmt);

        }

        memcpy(c->prev, c->cur, c->width * c->height * (c->bpp / 8));

    }

    *data_size = sizeof(AVFrame);

    *(AVFrame*)data = c->pic;

    /* always report that the buffer was completely consumed */

    return buf_size;

}

/*

 *

 * Init zmbv decoder

 *

 */

static av_cold int decode_init(AVCodecContext *avctx)

{

    ZmbvContext * const c = avctx->priv_data;

    int zret; // Zlib return code

    c->avctx = avctx;

    c->width = avctx->width;

    c->height = avctx->height;

    c->bpp = avctx->bits_per_coded_sample;

    // Needed if zlib unused or init aborted before inflateInit

    memset(&(c->zstream), 0, sizeof(z_stream));

    avctx->pix_fmt = PIX_FMT_RGB24;

    c->decomp_size = (avctx->width + 255) * 4 * (avctx->height + 64);

    /* Allocate decompression buffer */

    if (c->decomp_size) {

        if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) {

            av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");

            return 1;

        }

    }

    c->zstream.zalloc = Z_NULL;

    c->zstream.zfree = Z_NULL;

    c->zstream.opaque = Z_NULL;

    zret = inflateInit(&(c->zstream));

    if (zret != Z_OK) {

        av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);

        return 1;

    }

    return 0;

}

/*

 *

 * Uninit zmbv decoder

 *

 */

static av_cold int decode_end(AVCodecContext *avctx)

{

    ZmbvContext * const c = avctx->priv_data;

    av_freep(&c->decomp_buf);

    if (c->pic.data[0])

        avctx->release_buffer(avctx, &c->pic);

    inflateEnd(&(c->zstream));

    av_freep(&c->cur);

    av_freep(&c->prev);

    return 0;

}

AVCodec ff_zmbv_decoder = {

    "zmbv",

    AVMEDIA_TYPE_VIDEO,

    CODEC_ID_ZMBV,

    sizeof(ZmbvContext),

    decode_init,

    NULL,

    decode_end,

    decode_frame,

    CODEC_CAP_DR1,

    .long_name = NULL_IF_CONFIG_SMALL("Zip Motion Blocks Video"),

};