1/*
2 * Sony PlayStation MDEC (Motion DECoder)
3 * Copyright (c) 2003 Michael Niedermayer
4 *
5 * based upon code from Sebastian Jedruszkiewicz <elf@frogger.rules.pl>
6 *
7 * This file is part of Libav.
8 *
9 * Libav is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * Libav is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with Libav; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24/**
25 * @file
26 * Sony PlayStation MDEC (Motion DECoder)
27 * This is very similar to intra-only MPEG-1.
28 */
29
30#include "avcodec.h"
31#include "dsputil.h"
32#include "mpegvideo.h"
33#include "mpeg12.h"
34#include "thread.h"
35
36typedef struct MDECContext{
37    AVCodecContext *avctx;
38    DSPContext dsp;
39    AVFrame picture;
40    GetBitContext gb;
41    ScanTable scantable;
42    int version;
43    int qscale;
44    int last_dc[3];
45    int mb_width;
46    int mb_height;
47    int mb_x, mb_y;
48    DECLARE_ALIGNED(16, DCTELEM, block)[6][64];
49    uint8_t *bitstream_buffer;
50    unsigned int bitstream_buffer_size;
51    int block_last_index[6];
52} MDECContext;
53
54//very similar to MPEG-1
55static inline int mdec_decode_block_intra(MDECContext *a, DCTELEM *block, int n)
56{
57    int level, diff, i, j, run;
58    int component;
59    RLTable *rl = &ff_rl_mpeg1;
60    uint8_t * const scantable= a->scantable.permutated;
61    const uint16_t *quant_matrix= ff_mpeg1_default_intra_matrix;
62    const int qscale= a->qscale;
63
64    /* DC coefficient */
65    if(a->version==2){
66        block[0]= 2*get_sbits(&a->gb, 10) + 1024;
67    }else{
68        component = (n <= 3 ? 0 : n - 4 + 1);
69        diff = decode_dc(&a->gb, component);
70        if (diff >= 0xffff)
71            return -1;
72        a->last_dc[component]+= diff;
73        block[0] = a->last_dc[component]<<3;
74    }
75
76    i = 0;
77    {
78        OPEN_READER(re, &a->gb);
79        /* now quantify & encode AC coefficients */
80        for(;;) {
81            UPDATE_CACHE(re, &a->gb);
82            GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
83
84            if(level == 127){
85                break;
86            } else if(level != 0) {
87                i += run;
88                j = scantable[i];
89                level= (level*qscale*quant_matrix[j])>>3;
90                level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
91                LAST_SKIP_BITS(re, &a->gb, 1);
92            } else {
93                /* escape */
94                run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
95                UPDATE_CACHE(re, &a->gb);
96                level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
97                i += run;
98                j = scantable[i];
99                if(level<0){
100                    level= -level;
101                    level= (level*qscale*quant_matrix[j])>>3;
102                    level= (level-1)|1;
103                    level= -level;
104                }else{
105                    level= (level*qscale*quant_matrix[j])>>3;
106                    level= (level-1)|1;
107                }
108            }
109            if (i > 63){
110                av_log(a->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
111                return -1;
112            }
113
114            block[j] = level;
115        }
116        CLOSE_READER(re, &a->gb);
117    }
118    a->block_last_index[n] = i;
119    return 0;
120}
121
122static inline int decode_mb(MDECContext *a, DCTELEM block[6][64]){
123    int i;
124    const int block_index[6]= {5,4,0,1,2,3};
125
126    a->dsp.clear_blocks(block[0]);
127
128    for(i=0; i<6; i++){
129        if( mdec_decode_block_intra(a, block[ block_index[i] ], block_index[i]) < 0 ||
130            get_bits_left(&a->gb) < 0)
131            return -1;
132    }
133    return 0;
134}
135
136static inline void idct_put(MDECContext *a, int mb_x, int mb_y){
137    DCTELEM (*block)[64]= a->block;
138    int linesize= a->picture.linesize[0];
139
140    uint8_t *dest_y  = a->picture.data[0] + (mb_y * 16* linesize              ) + mb_x * 16;
141    uint8_t *dest_cb = a->picture.data[1] + (mb_y * 8 * a->picture.linesize[1]) + mb_x * 8;
142    uint8_t *dest_cr = a->picture.data[2] + (mb_y * 8 * a->picture.linesize[2]) + mb_x * 8;
143
144    a->dsp.idct_put(dest_y                 , linesize, block[0]);
145    a->dsp.idct_put(dest_y              + 8, linesize, block[1]);
146    a->dsp.idct_put(dest_y + 8*linesize    , linesize, block[2]);
147    a->dsp.idct_put(dest_y + 8*linesize + 8, linesize, block[3]);
148
149    if(!(a->avctx->flags&CODEC_FLAG_GRAY)){
150        a->dsp.idct_put(dest_cb, a->picture.linesize[1], block[4]);
151        a->dsp.idct_put(dest_cr, a->picture.linesize[2], block[5]);
152    }
153}
154
155static int decode_frame(AVCodecContext *avctx,
156                        void *data, int *data_size,
157                        AVPacket *avpkt)
158{
159    const uint8_t *buf = avpkt->data;
160    int buf_size = avpkt->size;
161    MDECContext * const a = avctx->priv_data;
162    AVFrame *picture = data;
163    AVFrame * const p= &a->picture;
164    int i;
165
166    if(p->data[0])
167        ff_thread_release_buffer(avctx, p);
168
169    p->reference= 0;
170    if(ff_thread_get_buffer(avctx, p) < 0){
171        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
172        return -1;
173    }
174    p->pict_type= AV_PICTURE_TYPE_I;
175    p->key_frame= 1;
176
177    av_fast_malloc(&a->bitstream_buffer, &a->bitstream_buffer_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
178    if (!a->bitstream_buffer)
179        return AVERROR(ENOMEM);
180    for(i=0; i<buf_size; i+=2){
181        a->bitstream_buffer[i]  = buf[i+1];
182        a->bitstream_buffer[i+1]= buf[i  ];
183    }
184    init_get_bits(&a->gb, a->bitstream_buffer, buf_size*8);
185
186    /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
187    skip_bits(&a->gb, 32);
188
189    a->qscale=  get_bits(&a->gb, 16);
190    a->version= get_bits(&a->gb, 16);
191
192    a->last_dc[0]=
193    a->last_dc[1]=
194    a->last_dc[2]= 128;
195
196    for(a->mb_x=0; a->mb_x<a->mb_width; a->mb_x++){
197        for(a->mb_y=0; a->mb_y<a->mb_height; a->mb_y++){
198            if( decode_mb(a, a->block) <0)
199                return -1;
200
201            idct_put(a, a->mb_x, a->mb_y);
202        }
203    }
204
205    p->quality= a->qscale * FF_QP2LAMBDA;
206    memset(p->qscale_table, a->qscale, a->mb_width);
207
208    *picture   = a->picture;
209    *data_size = sizeof(AVPicture);
210
211    return (get_bits_count(&a->gb)+31)/32*4;
212}
213
214static av_cold void mdec_common_init(AVCodecContext *avctx){
215    MDECContext * const a = avctx->priv_data;
216
217    dsputil_init(&a->dsp, avctx);
218
219    a->mb_width   = (avctx->coded_width  + 15) / 16;
220    a->mb_height  = (avctx->coded_height + 15) / 16;
221
222    avctx->coded_frame= &a->picture;
223    a->avctx= avctx;
224}
225
226static av_cold int decode_init(AVCodecContext *avctx){
227    MDECContext * const a = avctx->priv_data;
228    AVFrame *p= &a->picture;
229
230    mdec_common_init(avctx);
231    ff_mpeg12_init_vlcs();
232    ff_init_scantable(a->dsp.idct_permutation, &a->scantable, ff_zigzag_direct);
233
234    if( avctx->idct_algo == FF_IDCT_AUTO )
235        avctx->idct_algo = FF_IDCT_SIMPLE;
236    p->qstride= 0;
237    p->qscale_table= av_mallocz(a->mb_width);
238    avctx->pix_fmt= PIX_FMT_YUVJ420P;
239
240    return 0;
241}
242
243static av_cold int decode_init_thread_copy(AVCodecContext *avctx){
244    MDECContext * const a = avctx->priv_data;
245    AVFrame *p = (AVFrame*)&a->picture;
246
247    avctx->coded_frame = p;
248    a->avctx= avctx;
249
250    p->qscale_table = av_mallocz( a->mb_width);
251
252    return 0;
253}
254
255static av_cold int decode_end(AVCodecContext *avctx){
256    MDECContext * const a = avctx->priv_data;
257
258    if(a->picture.data[0])
259        avctx->release_buffer(avctx, &a->picture);
260    av_freep(&a->bitstream_buffer);
261    av_freep(&a->picture.qscale_table);
262    a->bitstream_buffer_size=0;
263
264    return 0;
265}
266
267AVCodec ff_mdec_decoder = {
268    .name           = "mdec",
269    .type           = AVMEDIA_TYPE_VIDEO,
270    .id             = CODEC_ID_MDEC,
271    .priv_data_size = sizeof(MDECContext),
272    .init           = decode_init,
273    .close          = decode_end,
274    .decode         = decode_frame,
275    .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
276    .long_name= NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"),
277    .init_thread_copy= ONLY_IF_THREADS_ENABLED(decode_init_thread_copy)
278};
279
280