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 #define BITSTREAM_READER_LE
32 
33 #include "libavutil/mem_internal.h"
34 
35 #include "aandcttab.h"
36 #include "avcodec.h"
37 #include "bytestream.h"
38 #include "codec_internal.h"
39 #include "eaidct.h"
40 #include "get_bits.h"
41 #include "idctdsp.h"
42 #include "internal.h"
43 
44 typedef struct TgqContext {
45     AVCodecContext *avctx;
46     int width, height;
47     ScanTable scantable;
48     int qtable[64];
49     DECLARE_ALIGNED(16, int16_t, block)[6][64];
50     GetByteContext gb;
51 } TgqContext;
52 
tgq_decode_init(AVCodecContext *avctx)53 static av_cold int tgq_decode_init(AVCodecContext *avctx)
54 {
55     TgqContext *s = avctx->priv_data;
56     uint8_t idct_permutation[64];
57     s->avctx = avctx;
58     ff_init_scantable_permutation(idct_permutation, FF_IDCT_PERM_NONE);
59     ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
60     avctx->framerate = (AVRational){ 15, 1 };
61     avctx->pix_fmt   = AV_PIX_FMT_YUV420P;
62     return 0;
63 }
64 
tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)65 static int tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
66 {
67     uint8_t *perm = s->scantable.permutated;
68     int i, j, value;
69     block[0] = get_sbits(gb, 8) * s->qtable[0];
70     for (i = 1; i < 64;) {
71         switch (show_bits(gb, 3)) {
72         case 4:
73             if (i >= 63)
74                 return AVERROR_INVALIDDATA;
75             block[perm[i++]] = 0;
76         case 0:
77             block[perm[i++]] = 0;
78             skip_bits(gb, 3);
79             break;
80         case 5:
81         case 1:
82             skip_bits(gb, 2);
83             value = get_bits(gb, 6);
84             if (value > 64 - i)
85                 return AVERROR_INVALIDDATA;
86             for (j = 0; j < value; j++)
87                 block[perm[i++]] = 0;
88             break;
89         case 6:
90             skip_bits(gb, 3);
91             block[perm[i]] = -s->qtable[perm[i]];
92             i++;
93             break;
94         case 2:
95             skip_bits(gb, 3);
96             block[perm[i]] = s->qtable[perm[i]];
97             i++;
98             break;
99         case 7: // 111b
100         case 3: // 011b
101             skip_bits(gb, 2);
102             if (show_bits(gb, 6) == 0x3F) {
103                 skip_bits(gb, 6);
104                 block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
105             } else {
106                 block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
107             }
108             i++;
109             break;
110         }
111     }
112     block[0] += 128 << 4;
113     return 0;
114 }
115 
tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame, int mb_x, int mb_y)116 static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame,
117                             int mb_x, int mb_y)
118 {
119     ptrdiff_t linesize = frame->linesize[0];
120     uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)           + mb_x * 16;
121     uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
122     uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
123 
124     ff_ea_idct_put_c(dest_y                   , linesize, block[0]);
125     ff_ea_idct_put_c(dest_y                + 8, linesize, block[1]);
126     ff_ea_idct_put_c(dest_y + 8 * linesize    , linesize, block[2]);
127     ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
128     if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
129          ff_ea_idct_put_c(dest_cb, frame->linesize[1], block[4]);
130          ff_ea_idct_put_c(dest_cr, frame->linesize[2], block[5]);
131     }
132 }
133 
tgq_dconly(TgqContext *s, unsigned char *dst, ptrdiff_t dst_stride, int dc)134 static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
135                               ptrdiff_t dst_stride, int dc)
136 {
137     int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
138     int j;
139     for (j = 0; j < 8; j++)
140         memset(dst + j * dst_stride, level, 8);
141 }
142 
tgq_idct_put_mb_dconly(TgqContext *s, AVFrame *frame, int mb_x, int mb_y, const int8_t *dc)143 static void tgq_idct_put_mb_dconly(TgqContext *s, AVFrame *frame,
144                                    int mb_x, int mb_y, const int8_t *dc)
145 {
146     ptrdiff_t linesize = frame->linesize[0];
147     uint8_t *dest_y  = frame->data[0] + (mb_y * 16 * linesize)             + mb_x * 16;
148     uint8_t *dest_cb = frame->data[1] + (mb_y * 8  * frame->linesize[1]) + mb_x * 8;
149     uint8_t *dest_cr = frame->data[2] + (mb_y * 8  * frame->linesize[2]) + mb_x * 8;
150     tgq_dconly(s, dest_y,                    linesize, dc[0]);
151     tgq_dconly(s, dest_y                + 8, linesize, dc[1]);
152     tgq_dconly(s, dest_y + 8 * linesize,     linesize, dc[2]);
153     tgq_dconly(s, dest_y + 8 * linesize + 8, linesize, dc[3]);
154     if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
155         tgq_dconly(s, dest_cb, frame->linesize[1], dc[4]);
156         tgq_dconly(s, dest_cr, frame->linesize[2], dc[5]);
157     }
158 }
159 
tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)160 static int tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)
161 {
162     int mode;
163     int i;
164     int8_t dc[6];
165 
166     mode = bytestream2_get_byte(&s->gb);
167     if (mode > 12) {
168         GetBitContext gb;
169         int ret = init_get_bits8(&gb, s->gb.buffer, FFMIN(bytestream2_get_bytes_left(&s->gb), mode));
170         if (ret < 0)
171             return ret;
172 
173         for (i = 0; i < 6; i++) {
174             int ret = tgq_decode_block(s, s->block[i], &gb);
175             if (ret < 0)
176                 return ret;
177         }
178         tgq_idct_put_mb(s, s->block, frame, mb_x, mb_y);
179         bytestream2_skip(&s->gb, mode);
180     } else {
181         if (mode == 3) {
182             memset(dc, bytestream2_get_byte(&s->gb), 4);
183             dc[4] = bytestream2_get_byte(&s->gb);
184             dc[5] = bytestream2_get_byte(&s->gb);
185         } else if (mode == 6) {
186             bytestream2_get_buffer(&s->gb, dc, 6);
187         } else if (mode == 12) {
188             for (i = 0; i < 6; i++) {
189                 dc[i] = bytestream2_get_byte(&s->gb);
190                 bytestream2_skip(&s->gb, 1);
191             }
192         } else {
193             av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
194             return -1;
195         }
196         tgq_idct_put_mb_dconly(s, frame, mb_x, mb_y, dc);
197     }
198     return 0;
199 }
200 
tgq_calculate_qtable(TgqContext *s, int quant)201 static void tgq_calculate_qtable(TgqContext *s, int quant)
202 {
203     int i, j;
204     const int a = (14 * (100 - quant)) / 100 + 1;
205     const int b = (11 * (100 - quant)) / 100 + 4;
206     for (j = 0; j < 8; j++)
207         for (i = 0; i < 8; i++)
208             s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
209                                     ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
210 }
211 
tgq_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)212 static int tgq_decode_frame(AVCodecContext *avctx, AVFrame *frame,
213                             int *got_frame, AVPacket *avpkt)
214 {
215     const uint8_t *buf = avpkt->data;
216     int buf_size       = avpkt->size;
217     TgqContext *s      = avctx->priv_data;
218     int x, y, ret;
219     int big_endian;
220 
221     if (buf_size < 16) {
222         av_log(avctx, AV_LOG_WARNING, "truncated header\n");
223         return AVERROR_INVALIDDATA;
224     }
225     big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
226     bytestream2_init(&s->gb, buf + 8, buf_size - 8);
227     if (big_endian) {
228         s->width  = bytestream2_get_be16u(&s->gb);
229         s->height = bytestream2_get_be16u(&s->gb);
230     } else {
231         s->width  = bytestream2_get_le16u(&s->gb);
232         s->height = bytestream2_get_le16u(&s->gb);
233     }
234 
235     ret = ff_set_dimensions(s->avctx, s->width, s->height);
236     if (ret < 0)
237         return ret;
238 
239     tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
240     bytestream2_skip(&s->gb, 3);
241 
242     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
243         return ret;
244     frame->key_frame = 1;
245     frame->pict_type = AV_PICTURE_TYPE_I;
246 
247     for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
248         for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
249             if (tgq_decode_mb(s, frame, y, x) < 0)
250                 return AVERROR_INVALIDDATA;
251 
252     *got_frame = 1;
253 
254     return avpkt->size;
255 }
256 
257 const FFCodec ff_eatgq_decoder = {
258     .p.name         = "eatgq",
259     .p.long_name    = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
260     .p.type         = AVMEDIA_TYPE_VIDEO,
261     .p.id           = AV_CODEC_ID_TGQ,
262     .priv_data_size = sizeof(TgqContext),
263     .init           = tgq_decode_init,
264     FF_CODEC_DECODE_CB(tgq_decode_frame),
265     .p.capabilities = AV_CODEC_CAP_DR1,
266     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
267 };
268