1/*
2 * Electronic Arts TGQ Video Decoder
3 * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
20 */
21
22/**
23 * @file
24 * Electronic Arts TGQ Video Decoder
25 * @author Peter Ross <pross@xvid.org>
26 *
27 * Technical details here:
28 * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGQ
29 */
30
31#include "avcodec.h"
32#define BITSTREAM_READER_LE
33#include "get_bits.h"
34#include "bytestream.h"
35#include "idctdsp.h"
36#include "aandcttab.h"
37#include "eaidct.h"
38#include "internal.h"
39
40typedef struct TgqContext {
41    AVCodecContext *avctx;
42    int width, height;
43    ScanTable scantable;
44    int qtable[64];
45    DECLARE_ALIGNED(16, int16_t, block)[6][64];
46    GetByteContext gb;
47} TgqContext;
48
49static av_cold int tgq_decode_init(AVCodecContext *avctx)
50{
51    TgqContext *s = avctx->priv_data;
52    uint8_t idct_permutation[64];
53    s->avctx = avctx;
54    ff_init_scantable_permutation(idct_permutation, FF_NO_IDCT_PERM);
55    ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
56    avctx->time_base = (AVRational){1, 15};
57    avctx->pix_fmt   = AV_PIX_FMT_YUV420P;
58    return 0;
59}
60
61static void tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
62{
63    uint8_t *perm = s->scantable.permutated;
64    int i, j, value;
65    block[0] = get_sbits(gb, 8) * s->qtable[0];
66    for (i = 1; i < 64;) {
67        switch (show_bits(gb, 3)) {
68        case 4:
69            block[perm[i++]] = 0;
70        case 0:
71            block[perm[i++]] = 0;
72            skip_bits(gb, 3);
73            break;
74        case 5:
75        case 1:
76            skip_bits(gb, 2);
77            value = get_bits(gb, 6);
78            for (j = 0; j < value; j++)
79                block[perm[i++]] = 0;
80            break;
81        case 6:
82            skip_bits(gb, 3);
83            block[perm[i]] = -s->qtable[perm[i]];
84            i++;
85            break;
86        case 2:
87            skip_bits(gb, 3);
88            block[perm[i]] = s->qtable[perm[i]];
89            i++;
90            break;
91        case 7: // 111b
92        case 3: // 011b
93            skip_bits(gb, 2);
94            if (show_bits(gb, 6) == 0x3F) {
95                skip_bits(gb, 6);
96                block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
97            } else {
98                block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
99            }
100            i++;
101            break;
102        }
103    }
104    block[0] += 128 << 4;
105}
106
107static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame,
108                            int mb_x, int mb_y)
109{
110    int linesize = frame->linesize[0];
111    uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)           + mb_x * 16;
112    uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
113    uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
114
115    ff_ea_idct_put_c(dest_y                   , linesize, block[0]);
116    ff_ea_idct_put_c(dest_y                + 8, linesize, block[1]);
117    ff_ea_idct_put_c(dest_y + 8 * linesize    , linesize, block[2]);
118    ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
119    if (!(s->avctx->flags & CODEC_FLAG_GRAY)) {
120         ff_ea_idct_put_c(dest_cb, frame->linesize[1], block[4]);
121         ff_ea_idct_put_c(dest_cr, frame->linesize[2], block[5]);
122    }
123}
124
125static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
126                              int dst_stride, int dc)
127{
128    int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
129    int j;
130    for (j = 0; j < 8; j++)
131        memset(dst + j * dst_stride, level, 8);
132}
133
134static void tgq_idct_put_mb_dconly(TgqContext *s, AVFrame *frame,
135                                   int mb_x, int mb_y, const int8_t *dc)
136{
137    int linesize = frame->linesize[0];
138    uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)             + mb_x * 16;
139    uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
140    uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
141    tgq_dconly(s, dest_y,                    linesize, dc[0]);
142    tgq_dconly(s, dest_y                + 8, linesize, dc[1]);
143    tgq_dconly(s, dest_y + 8 * linesize,     linesize, dc[2]);
144    tgq_dconly(s, dest_y + 8 * linesize + 8, linesize, dc[3]);
145    if (!(s->avctx->flags & CODEC_FLAG_GRAY)) {
146        tgq_dconly(s, dest_cb, frame->linesize[1], dc[4]);
147        tgq_dconly(s, dest_cr, frame->linesize[2], dc[5]);
148    }
149}
150
151static int tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)
152{
153    int mode;
154    int i;
155    int8_t dc[6];
156
157    mode = bytestream2_get_byte(&s->gb);
158    if (mode > 12) {
159        GetBitContext gb;
160        init_get_bits8(&gb, s->gb.buffer, FFMIN(bytestream2_get_bytes_left(&s->gb), mode));
161        for (i = 0; i < 6; i++)
162            tgq_decode_block(s, s->block[i], &gb);
163        tgq_idct_put_mb(s, s->block, frame, mb_x, mb_y);
164        bytestream2_skip(&s->gb, mode);
165    } else {
166        if (mode == 3) {
167            memset(dc, bytestream2_get_byte(&s->gb), 4);
168            dc[4] = bytestream2_get_byte(&s->gb);
169            dc[5] = bytestream2_get_byte(&s->gb);
170        } else if (mode == 6) {
171            bytestream2_get_buffer(&s->gb, dc, 6);
172        } else if (mode == 12) {
173            for (i = 0; i < 6; i++) {
174                dc[i] = bytestream2_get_byte(&s->gb);
175                bytestream2_skip(&s->gb, 1);
176            }
177        } else {
178            av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
179            return -1;
180        }
181        tgq_idct_put_mb_dconly(s, frame, mb_x, mb_y, dc);
182    }
183    return 0;
184}
185
186static void tgq_calculate_qtable(TgqContext *s, int quant)
187{
188    int i, j;
189    const int a = (14 * (100 - quant)) / 100 + 1;
190    const int b = (11 * (100 - quant)) / 100 + 4;
191    for (j = 0; j < 8; j++)
192        for (i = 0; i < 8; i++)
193            s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
194                                    ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
195}
196
197static int tgq_decode_frame(AVCodecContext *avctx,
198                            void *data, int *got_frame,
199                            AVPacket *avpkt)
200{
201    const uint8_t *buf = avpkt->data;
202    int buf_size       = avpkt->size;
203    TgqContext *s      = avctx->priv_data;
204    AVFrame *frame     = data;
205    int x, y, ret;
206    int big_endian;
207
208    if (buf_size < 16) {
209        av_log(avctx, AV_LOG_WARNING, "truncated header\n");
210        return AVERROR_INVALIDDATA;
211    }
212    big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
213    bytestream2_init(&s->gb, buf + 8, buf_size - 8);
214    if (big_endian) {
215        s->width  = bytestream2_get_be16u(&s->gb);
216        s->height = bytestream2_get_be16u(&s->gb);
217    } else {
218        s->width  = bytestream2_get_le16u(&s->gb);
219        s->height = bytestream2_get_le16u(&s->gb);
220    }
221
222    ret = ff_set_dimensions(s->avctx, s->width, s->height);
223    if (ret < 0)
224        return ret;
225
226    tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
227    bytestream2_skip(&s->gb, 3);
228
229    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
230        return ret;
231    frame->key_frame = 1;
232    frame->pict_type = AV_PICTURE_TYPE_I;
233
234    for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
235        for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
236            if (tgq_decode_mb(s, frame, y, x) < 0)
237                return AVERROR_INVALIDDATA;
238
239    *got_frame = 1;
240
241    return avpkt->size;
242}
243
244AVCodec ff_eatgq_decoder = {
245    .name           = "eatgq",
246    .long_name      = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
247    .type           = AVMEDIA_TYPE_VIDEO,
248    .id             = AV_CODEC_ID_TGQ,
249    .priv_data_size = sizeof(TgqContext),
250    .init           = tgq_decode_init,
251    .decode         = tgq_decode_frame,
252    .capabilities   = CODEC_CAP_DR1,
253};
254