yading@10: /*
yading@10:  * KMVC decoder
yading@10:  * Copyright (c) 2006 Konstantin Shishkov
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * Karl Morton's Video Codec decoder
yading@10:  */
yading@10: 
yading@10: #include <stdio.h>
yading@10: #include <stdlib.h>
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "bytestream.h"
yading@10: #include "internal.h"
yading@10: 
yading@10: #define KMVC_KEYFRAME 0x80
yading@10: #define KMVC_PALETTE  0x40
yading@10: #define KMVC_METHOD   0x0F
yading@10: #define MAX_PALSIZE   256
yading@10: 
yading@10: /*
yading@10:  * Decoder context
yading@10:  */
yading@10: typedef struct KmvcContext {
yading@10:     AVCodecContext *avctx;
yading@10: 
yading@10:     int setpal;
yading@10:     int palsize;
yading@10:     uint32_t pal[MAX_PALSIZE];
yading@10:     uint8_t *cur, *prev;
yading@10:     uint8_t *frm0, *frm1;
yading@10:     GetByteContext g;
yading@10: } KmvcContext;
yading@10: 
yading@10: typedef struct BitBuf {
yading@10:     int bits;
yading@10:     int bitbuf;
yading@10: } BitBuf;
yading@10: 
yading@10: #define BLK(data, x, y)  data[(x) + (y) * 320]
yading@10: 
yading@10: #define kmvc_init_getbits(bb, g)  bb.bits = 7; bb.bitbuf = bytestream2_get_byte(g);
yading@10: 
yading@10: #define kmvc_getbit(bb, g, res) {\
yading@10:     res = 0; \
yading@10:     if (bb.bitbuf & (1 << bb.bits)) res = 1; \
yading@10:     bb.bits--; \
yading@10:     if(bb.bits == -1) { \
yading@10:         bb.bitbuf = bytestream2_get_byte(g); \
yading@10:         bb.bits = 7; \
yading@10:     } \
yading@10: }
yading@10: 
yading@10: static int kmvc_decode_intra_8x8(KmvcContext * ctx, int w, int h)
yading@10: {
yading@10:     BitBuf bb;
yading@10:     int res, val;
yading@10:     int i, j;
yading@10:     int bx, by;
yading@10:     int l0x, l1x, l0y, l1y;
yading@10:     int mx, my;
yading@10: 
yading@10:     kmvc_init_getbits(bb, &ctx->g);
yading@10: 
yading@10:     for (by = 0; by < h; by += 8)
yading@10:         for (bx = 0; bx < w; bx += 8) {
yading@10:             if (!bytestream2_get_bytes_left(&ctx->g)) {
yading@10:                 av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n");
yading@10:                 return AVERROR_INVALIDDATA;
yading@10:             }
yading@10:             kmvc_getbit(bb, &ctx->g, res);
yading@10:             if (!res) {         // fill whole 8x8 block
yading@10:                 val = bytestream2_get_byte(&ctx->g);
yading@10:                 for (i = 0; i < 64; i++)
yading@10:                     BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = val;
yading@10:             } else {            // handle four 4x4 subblocks
yading@10:                 for (i = 0; i < 4; i++) {
yading@10:                     l0x = bx + (i & 1) * 4;
yading@10:                     l0y = by + (i & 2) * 2;
yading@10:                     kmvc_getbit(bb, &ctx->g, res);
yading@10:                     if (!res) {
yading@10:                         kmvc_getbit(bb, &ctx->g, res);
yading@10:                         if (!res) {     // fill whole 4x4 block
yading@10:                             val = bytestream2_get_byte(&ctx->g);
yading@10:                             for (j = 0; j < 16; j++)
yading@10:                                 BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = val;
yading@10:                         } else {        // copy block from already decoded place
yading@10:                             val = bytestream2_get_byte(&ctx->g);
yading@10:                             mx = val & 0xF;
yading@10:                             my = val >> 4;
yading@10:                             if ((l0x-mx) + 320*(l0y-my) < 0 || (l0x-mx) + 320*(l0y-my) > 316*196) {
yading@10:                                 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n");
yading@10:                                 return AVERROR_INVALIDDATA;
yading@10:                             }
yading@10:                             for (j = 0; j < 16; j++)
yading@10:                                 BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) =
yading@10:                                     BLK(ctx->cur, l0x + (j & 3) - mx, l0y + (j >> 2) - my);
yading@10:                         }
yading@10:                     } else {    // descend to 2x2 sub-sub-blocks
yading@10:                         for (j = 0; j < 4; j++) {
yading@10:                             l1x = l0x + (j & 1) * 2;
yading@10:                             l1y = l0y + (j & 2);
yading@10:                             kmvc_getbit(bb, &ctx->g, res);
yading@10:                             if (!res) {
yading@10:                                 kmvc_getbit(bb, &ctx->g, res);
yading@10:                                 if (!res) {     // fill whole 2x2 block
yading@10:                                     val = bytestream2_get_byte(&ctx->g);
yading@10:                                     BLK(ctx->cur, l1x, l1y) = val;
yading@10:                                     BLK(ctx->cur, l1x + 1, l1y) = val;
yading@10:                                     BLK(ctx->cur, l1x, l1y + 1) = val;
yading@10:                                     BLK(ctx->cur, l1x + 1, l1y + 1) = val;
yading@10:                                 } else {        // copy block from already decoded place
yading@10:                                     val = bytestream2_get_byte(&ctx->g);
yading@10:                                     mx = val & 0xF;
yading@10:                                     my = val >> 4;
yading@10:                                     if ((l1x-mx) + 320*(l1y-my) < 0 || (l1x-mx) + 320*(l1y-my) > 318*198) {
yading@10:                                         av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n");
yading@10:                                         return AVERROR_INVALIDDATA;
yading@10:                                     }
yading@10:                                     BLK(ctx->cur, l1x, l1y) = BLK(ctx->cur, l1x - mx, l1y - my);
yading@10:                                     BLK(ctx->cur, l1x + 1, l1y) =
yading@10:                                         BLK(ctx->cur, l1x + 1 - mx, l1y - my);
yading@10:                                     BLK(ctx->cur, l1x, l1y + 1) =
yading@10:                                         BLK(ctx->cur, l1x - mx, l1y + 1 - my);
yading@10:                                     BLK(ctx->cur, l1x + 1, l1y + 1) =
yading@10:                                         BLK(ctx->cur, l1x + 1 - mx, l1y + 1 - my);
yading@10:                                 }
yading@10:                             } else {    // read values for block
yading@10:                                 BLK(ctx->cur, l1x, l1y) = bytestream2_get_byte(&ctx->g);
yading@10:                                 BLK(ctx->cur, l1x + 1, l1y) = bytestream2_get_byte(&ctx->g);
yading@10:                                 BLK(ctx->cur, l1x, l1y + 1) = bytestream2_get_byte(&ctx->g);
yading@10:                                 BLK(ctx->cur, l1x + 1, l1y + 1) = bytestream2_get_byte(&ctx->g);
yading@10:                             }
yading@10:                         }
yading@10:                     }
yading@10:                 }
yading@10:             }
yading@10:         }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int kmvc_decode_inter_8x8(KmvcContext * ctx, int w, int h)
yading@10: {
yading@10:     BitBuf bb;
yading@10:     int res, val;
yading@10:     int i, j;
yading@10:     int bx, by;
yading@10:     int l0x, l1x, l0y, l1y;
yading@10:     int mx, my;
yading@10: 
yading@10:     kmvc_init_getbits(bb, &ctx->g);
yading@10: 
yading@10:     for (by = 0; by < h; by += 8)
yading@10:         for (bx = 0; bx < w; bx += 8) {
yading@10:             kmvc_getbit(bb, &ctx->g, res);
yading@10:             if (!res) {
yading@10:                 kmvc_getbit(bb, &ctx->g, res);
yading@10:                 if (!res) {     // fill whole 8x8 block
yading@10:                     if (!bytestream2_get_bytes_left(&ctx->g)) {
yading@10:                         av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n");
yading@10:                         return AVERROR_INVALIDDATA;
yading@10:                     }
yading@10:                     val = bytestream2_get_byte(&ctx->g);
yading@10:                     for (i = 0; i < 64; i++)
yading@10:                         BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = val;
yading@10:                 } else {        // copy block from previous frame
yading@10:                     for (i = 0; i < 64; i++)
yading@10:                         BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) =
yading@10:                             BLK(ctx->prev, bx + (i & 0x7), by + (i >> 3));
yading@10:                 }
yading@10:             } else {            // handle four 4x4 subblocks
yading@10:                 if (!bytestream2_get_bytes_left(&ctx->g)) {
yading@10:                     av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n");
yading@10:                     return AVERROR_INVALIDDATA;
yading@10:                 }
yading@10:                 for (i = 0; i < 4; i++) {
yading@10:                     l0x = bx + (i & 1) * 4;
yading@10:                     l0y = by + (i & 2) * 2;
yading@10:                     kmvc_getbit(bb, &ctx->g, res);
yading@10:                     if (!res) {
yading@10:                         kmvc_getbit(bb, &ctx->g, res);
yading@10:                         if (!res) {     // fill whole 4x4 block
yading@10:                             val = bytestream2_get_byte(&ctx->g);
yading@10:                             for (j = 0; j < 16; j++)
yading@10:                                 BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = val;
yading@10:                         } else {        // copy block
yading@10:                             val = bytestream2_get_byte(&ctx->g);
yading@10:                             mx = (val & 0xF) - 8;
yading@10:                             my = (val >> 4) - 8;
yading@10:                             if ((l0x+mx) + 320*(l0y+my) < 0 || (l0x+mx) + 320*(l0y+my) > 318*198) {
yading@10:                                 av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n");
yading@10:                                 return AVERROR_INVALIDDATA;
yading@10:                             }
yading@10:                             for (j = 0; j < 16; j++)
yading@10:                                 BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) =
yading@10:                                     BLK(ctx->prev, l0x + (j & 3) + mx, l0y + (j >> 2) + my);
yading@10:                         }
yading@10:                     } else {    // descend to 2x2 sub-sub-blocks
yading@10:                         for (j = 0; j < 4; j++) {
yading@10:                             l1x = l0x + (j & 1) * 2;
yading@10:                             l1y = l0y + (j & 2);
yading@10:                             kmvc_getbit(bb, &ctx->g, res);
yading@10:                             if (!res) {
yading@10:                                 kmvc_getbit(bb, &ctx->g, res);
yading@10:                                 if (!res) {     // fill whole 2x2 block
yading@10:                                     val = bytestream2_get_byte(&ctx->g);
yading@10:                                     BLK(ctx->cur, l1x, l1y) = val;
yading@10:                                     BLK(ctx->cur, l1x + 1, l1y) = val;
yading@10:                                     BLK(ctx->cur, l1x, l1y + 1) = val;
yading@10:                                     BLK(ctx->cur, l1x + 1, l1y + 1) = val;
yading@10:                                 } else {        // copy block
yading@10:                                     val = bytestream2_get_byte(&ctx->g);
yading@10:                                     mx = (val & 0xF) - 8;
yading@10:                                     my = (val >> 4) - 8;
yading@10:                                     if ((l1x+mx) + 320*(l1y+my) < 0 || (l1x+mx) + 320*(l1y+my) > 318*198) {
yading@10:                                         av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n");
yading@10:                                         return AVERROR_INVALIDDATA;
yading@10:                                     }
yading@10:                                     BLK(ctx->cur, l1x, l1y) = BLK(ctx->prev, l1x + mx, l1y + my);
yading@10:                                     BLK(ctx->cur, l1x + 1, l1y) =
yading@10:                                         BLK(ctx->prev, l1x + 1 + mx, l1y + my);
yading@10:                                     BLK(ctx->cur, l1x, l1y + 1) =
yading@10:                                         BLK(ctx->prev, l1x + mx, l1y + 1 + my);
yading@10:                                     BLK(ctx->cur, l1x + 1, l1y + 1) =
yading@10:                                         BLK(ctx->prev, l1x + 1 + mx, l1y + 1 + my);
yading@10:                                 }
yading@10:                             } else {    // read values for block
yading@10:                                 BLK(ctx->cur, l1x, l1y) = bytestream2_get_byte(&ctx->g);
yading@10:                                 BLK(ctx->cur, l1x + 1, l1y) = bytestream2_get_byte(&ctx->g);
yading@10:                                 BLK(ctx->cur, l1x, l1y + 1) = bytestream2_get_byte(&ctx->g);
yading@10:                                 BLK(ctx->cur, l1x + 1, l1y + 1) = bytestream2_get_byte(&ctx->g);
yading@10:                             }
yading@10:                         }
yading@10:                     }
yading@10:                 }
yading@10:             }
yading@10:         }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int decode_frame(AVCodecContext * avctx, void *data, int *got_frame,
yading@10:                         AVPacket *avpkt)
yading@10: {
yading@10:     KmvcContext *const ctx = avctx->priv_data;
yading@10:     AVFrame *frame = data;
yading@10:     uint8_t *out, *src;
yading@10:     int i, ret;
yading@10:     int header;
yading@10:     int blocksize;
yading@10:     const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
yading@10: 
yading@10:     bytestream2_init(&ctx->g, avpkt->data, avpkt->size);
yading@10: 
yading@10:     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     header = bytestream2_get_byte(&ctx->g);
yading@10: 
yading@10:     /* blocksize 127 is really palette change event */
yading@10:     if (bytestream2_peek_byte(&ctx->g) == 127) {
yading@10:         bytestream2_skip(&ctx->g, 3);
yading@10:         for (i = 0; i < 127; i++) {
yading@10:             ctx->pal[i + (header & 0x81)] = 0xFFU << 24 | bytestream2_get_be24(&ctx->g);
yading@10:             bytestream2_skip(&ctx->g, 1);
yading@10:         }
yading@10:         bytestream2_seek(&ctx->g, -127 * 4 - 3, SEEK_CUR);
yading@10:     }
yading@10: 
yading@10:     if (header & KMVC_KEYFRAME) {
yading@10:         frame->key_frame = 1;
yading@10:         frame->pict_type = AV_PICTURE_TYPE_I;
yading@10:     } else {
yading@10:         frame->key_frame = 0;
yading@10:         frame->pict_type = AV_PICTURE_TYPE_P;
yading@10:     }
yading@10: 
yading@10:     if (header & KMVC_PALETTE) {
yading@10:         frame->palette_has_changed = 1;
yading@10:         // palette starts from index 1 and has 127 entries
yading@10:         for (i = 1; i <= ctx->palsize; i++) {
yading@10:             ctx->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&ctx->g);
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     if (pal) {
yading@10:         frame->palette_has_changed = 1;
yading@10:         memcpy(ctx->pal, pal, AVPALETTE_SIZE);
yading@10:     }
yading@10: 
yading@10:     if (ctx->setpal) {
yading@10:         ctx->setpal = 0;
yading@10:         frame->palette_has_changed = 1;
yading@10:     }
yading@10: 
yading@10:     /* make the palette available on the way out */
yading@10:     memcpy(frame->data[1], ctx->pal, 1024);
yading@10: 
yading@10:     blocksize = bytestream2_get_byte(&ctx->g);
yading@10: 
yading@10:     if (blocksize != 8 && blocksize != 127) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Block size = %i\n", blocksize);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     memset(ctx->cur, 0, 320 * 200);
yading@10:     switch (header & KMVC_METHOD) {
yading@10:     case 0:
yading@10:     case 1: // used in palette changed event
yading@10:         memcpy(ctx->cur, ctx->prev, 320 * 200);
yading@10:         break;
yading@10:     case 3:
yading@10:         kmvc_decode_intra_8x8(ctx, avctx->width, avctx->height);
yading@10:         break;
yading@10:     case 4:
yading@10:         kmvc_decode_inter_8x8(ctx, avctx->width, avctx->height);
yading@10:         break;
yading@10:     default:
yading@10:         av_log(avctx, AV_LOG_ERROR, "Unknown compression method %i\n", header & KMVC_METHOD);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10: 
yading@10:     out = frame->data[0];
yading@10:     src = ctx->cur;
yading@10:     for (i = 0; i < avctx->height; i++) {
yading@10:         memcpy(out, src, avctx->width);
yading@10:         src += 320;
yading@10:         out += frame->linesize[0];
yading@10:     }
yading@10: 
yading@10:     /* flip buffers */
yading@10:     if (ctx->cur == ctx->frm0) {
yading@10:         ctx->cur = ctx->frm1;
yading@10:         ctx->prev = ctx->frm0;
yading@10:     } else {
yading@10:         ctx->cur = ctx->frm0;
yading@10:         ctx->prev = ctx->frm1;
yading@10:     }
yading@10: 
yading@10:     *got_frame = 1;
yading@10: 
yading@10:     /* always report that the buffer was completely consumed */
yading@10:     return avpkt->size;
yading@10: }
yading@10: 
yading@10: 
yading@10: 
yading@10: /*
yading@10:  * Init kmvc decoder
yading@10:  */
yading@10: static av_cold int decode_init(AVCodecContext * avctx)
yading@10: {
yading@10:     KmvcContext *const c = avctx->priv_data;
yading@10:     int i;
yading@10: 
yading@10:     c->avctx = avctx;
yading@10: 
yading@10:     if (avctx->width > 320 || avctx->height > 200) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "KMVC supports frames <= 320x200\n");
yading@10:         return AVERROR(EINVAL);
yading@10:     }
yading@10: 
yading@10:     c->frm0 = av_mallocz(320 * 200);
yading@10:     c->frm1 = av_mallocz(320 * 200);
yading@10:     c->cur = c->frm0;
yading@10:     c->prev = c->frm1;
yading@10: 
yading@10:     for (i = 0; i < 256; i++) {
yading@10:         c->pal[i] = 0xFFU << 24 | i * 0x10101;
yading@10:     }
yading@10: 
yading@10:     if (avctx->extradata_size < 12) {
yading@10:         av_log(avctx, AV_LOG_WARNING,
yading@10:                "Extradata missing, decoding may not work properly...\n");
yading@10:         c->palsize = 127;
yading@10:     } else {
yading@10:         c->palsize = AV_RL16(avctx->extradata + 10);
yading@10:         if (c->palsize >= (unsigned)MAX_PALSIZE) {
yading@10:             c->palsize = 127;
yading@10:             av_log(avctx, AV_LOG_ERROR, "KMVC palette too large\n");
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     if (avctx->extradata_size == 1036) {        // palette in extradata
yading@10:         uint8_t *src = avctx->extradata + 12;
yading@10:         for (i = 0; i < 256; i++) {
yading@10:             c->pal[i] = AV_RL32(src);
yading@10:             src += 4;
yading@10:         }
yading@10:         c->setpal = 1;
yading@10:     }
yading@10: 
yading@10:     avctx->pix_fmt = AV_PIX_FMT_PAL8;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: 
yading@10: 
yading@10: /*
yading@10:  * Uninit kmvc decoder
yading@10:  */
yading@10: static av_cold int decode_end(AVCodecContext * avctx)
yading@10: {
yading@10:     KmvcContext *const c = avctx->priv_data;
yading@10: 
yading@10:     av_freep(&c->frm0);
yading@10:     av_freep(&c->frm1);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_kmvc_decoder = {
yading@10:     .name           = "kmvc",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_KMVC,
yading@10:     .priv_data_size = sizeof(KmvcContext),
yading@10:     .init           = decode_init,
yading@10:     .close          = decode_end,
yading@10:     .decode         = decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("Karl Morton's video codec"),
yading@10: };