1/*
2 * Fraps FPS1 decoder
3 * Copyright (c) 2005 Roine Gustafsson
4 * Copyright (c) 2006 Konstantin Shishkov
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23/**
24 * @file libavcodec/fraps.c
25 * Lossless Fraps 'FPS1' decoder
26 * @author Roine Gustafsson <roine at users sf net>
27 * @author Konstantin Shishkov
28 *
29 * Codec algorithm for version 0 is taken from Transcode <www.transcoding.org>
30 *
31 * Version 2 files support by Konstantin Shishkov
32 */
33
34#include "avcodec.h"
35#include "bitstream.h"
36#include "huffman.h"
37#include "bytestream.h"
38#include "dsputil.h"
39
40#define FPS_TAG MKTAG('F', 'P', 'S', 'x')
41
42/**
43 * local variable storage
44 */
45typedef struct FrapsContext{
46    AVCodecContext *avctx;
47    AVFrame frame;
48    uint8_t *tmpbuf;
49    DSPContext dsp;
50} FrapsContext;
51
52
53/**
54 * initializes decoder
55 * @param avctx codec context
56 * @return 0 on success or negative if fails
57 */
58static av_cold int decode_init(AVCodecContext *avctx)
59{
60    FrapsContext * const s = avctx->priv_data;
61
62    avctx->coded_frame = (AVFrame*)&s->frame;
63    avctx->pix_fmt= PIX_FMT_NONE; /* set in decode_frame */
64
65    s->avctx = avctx;
66    s->frame.data[0] = NULL;
67    s->tmpbuf = NULL;
68
69    dsputil_init(&s->dsp, avctx);
70
71    return 0;
72}
73
74/**
75 * Comparator - our nodes should ascend by count
76 * but with preserved symbol order
77 */
78static int huff_cmp(const void *va, const void *vb){
79    const Node *a = va, *b = vb;
80    return (a->count - b->count)*256 + a->sym - b->sym;
81}
82
83/**
84 * decode Fraps v2 packed plane
85 */
86static int fraps2_decode_plane(FrapsContext *s, uint8_t *dst, int stride, int w,
87                               int h, const uint8_t *src, int size, int Uoff,
88                               const int step)
89{
90    int i, j;
91    GetBitContext gb;
92    VLC vlc;
93    Node nodes[512];
94
95    for(i = 0; i < 256; i++)
96        nodes[i].count = bytestream_get_le32(&src);
97    size -= 1024;
98    if (ff_huff_build_tree(s->avctx, &vlc, 256, nodes, huff_cmp,
99                           FF_HUFFMAN_FLAG_ZERO_COUNT) < 0)
100        return -1;
101    /* we have built Huffman table and are ready to decode plane */
102
103    /* convert bits so they may be used by standard bitreader */
104    s->dsp.bswap_buf((uint32_t *)s->tmpbuf, (const uint32_t *)src, size >> 2);
105
106    init_get_bits(&gb, s->tmpbuf, size * 8);
107    for(j = 0; j < h; j++){
108        for(i = 0; i < w*step; i += step){
109            dst[i] = get_vlc2(&gb, vlc.table, 9, 3);
110            /* lines are stored as deltas between previous lines
111             * and we need to add 0x80 to the first lines of chroma planes
112             */
113            if(j) dst[i] += dst[i - stride];
114            else if(Uoff) dst[i] += 0x80;
115        }
116        dst += stride;
117    }
118    free_vlc(&vlc);
119    return 0;
120}
121
122/**
123 * decode a frame
124 * @param avctx codec context
125 * @param data output AVFrame
126 * @param data_size size of output data or 0 if no picture is returned
127 * @param buf input data frame
128 * @param buf_size size of input data frame
129 * @return number of consumed bytes on success or negative if decode fails
130 */
131static int decode_frame(AVCodecContext *avctx,
132                        void *data, int *data_size,
133                        const uint8_t *buf, int buf_size)
134{
135    FrapsContext * const s = avctx->priv_data;
136    AVFrame *frame = data;
137    AVFrame * const f = (AVFrame*)&s->frame;
138    uint32_t header;
139    unsigned int version,header_size;
140    unsigned int x, y;
141    const uint32_t *buf32;
142    uint32_t *luma1,*luma2,*cb,*cr;
143    uint32_t offs[4];
144    int i, j, is_chroma, planes;
145
146
147    header = AV_RL32(buf);
148    version = header & 0xff;
149    header_size = (header & (1<<30))? 8 : 4; /* bit 30 means pad to 8 bytes */
150
151    if (version > 5) {
152        av_log(avctx, AV_LOG_ERROR,
153               "This file is encoded with Fraps version %d. " \
154               "This codec can only decode versions <= 5.\n", version);
155        return -1;
156    }
157
158    buf+=4;
159    if (header_size == 8)
160        buf+=4;
161
162    switch(version) {
163    case 0:
164    default:
165        /* Fraps v0 is a reordered YUV420 */
166        avctx->pix_fmt = PIX_FMT_YUV420P;
167
168        if ( (buf_size != avctx->width*avctx->height*3/2+header_size) &&
169             (buf_size != header_size) ) {
170            av_log(avctx, AV_LOG_ERROR,
171                   "Invalid frame length %d (should be %d)\n",
172                   buf_size, avctx->width*avctx->height*3/2+header_size);
173            return -1;
174        }
175
176        if (( (avctx->width % 8) != 0) || ( (avctx->height % 2) != 0 )) {
177            av_log(avctx, AV_LOG_ERROR, "Invalid frame size %dx%d\n",
178                   avctx->width, avctx->height);
179            return -1;
180        }
181
182        f->reference = 1;
183        f->buffer_hints = FF_BUFFER_HINTS_VALID |
184                          FF_BUFFER_HINTS_PRESERVE |
185                          FF_BUFFER_HINTS_REUSABLE;
186        if (avctx->reget_buffer(avctx, f)) {
187            av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
188            return -1;
189        }
190        /* bit 31 means same as previous pic */
191        f->pict_type = (header & (1<<31))? FF_P_TYPE : FF_I_TYPE;
192        f->key_frame = f->pict_type == FF_I_TYPE;
193
194        if (f->pict_type == FF_I_TYPE) {
195            buf32=(const uint32_t*)buf;
196            for(y=0; y<avctx->height/2; y++){
197                luma1=(uint32_t*)&f->data[0][ y*2*f->linesize[0] ];
198                luma2=(uint32_t*)&f->data[0][ (y*2+1)*f->linesize[0] ];
199                cr=(uint32_t*)&f->data[1][ y*f->linesize[1] ];
200                cb=(uint32_t*)&f->data[2][ y*f->linesize[2] ];
201                for(x=0; x<avctx->width; x+=8){
202                    *(luma1++) = *(buf32++);
203                    *(luma1++) = *(buf32++);
204                    *(luma2++) = *(buf32++);
205                    *(luma2++) = *(buf32++);
206                    *(cr++) = *(buf32++);
207                    *(cb++) = *(buf32++);
208                }
209            }
210        }
211        break;
212
213    case 1:
214        /* Fraps v1 is an upside-down BGR24 */
215        avctx->pix_fmt = PIX_FMT_BGR24;
216
217        if ( (buf_size != avctx->width*avctx->height*3+header_size) &&
218             (buf_size != header_size) ) {
219            av_log(avctx, AV_LOG_ERROR,
220                   "Invalid frame length %d (should be %d)\n",
221                   buf_size, avctx->width*avctx->height*3+header_size);
222            return -1;
223        }
224
225        f->reference = 1;
226        f->buffer_hints = FF_BUFFER_HINTS_VALID |
227                          FF_BUFFER_HINTS_PRESERVE |
228                          FF_BUFFER_HINTS_REUSABLE;
229        if (avctx->reget_buffer(avctx, f)) {
230            av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
231            return -1;
232        }
233        /* bit 31 means same as previous pic */
234        f->pict_type = (header & (1<<31))? FF_P_TYPE : FF_I_TYPE;
235        f->key_frame = f->pict_type == FF_I_TYPE;
236
237        if (f->pict_type == FF_I_TYPE) {
238            for(y=0; y<avctx->height; y++)
239                memcpy(&f->data[0][ (avctx->height-y)*f->linesize[0] ],
240                       &buf[y*avctx->width*3],
241                       f->linesize[0]);
242        }
243        break;
244
245    case 2:
246    case 4:
247        /**
248         * Fraps v2 is Huffman-coded YUV420 planes
249         * Fraps v4 is virtually the same
250         */
251        avctx->pix_fmt = PIX_FMT_YUV420P;
252        planes = 3;
253        f->reference = 1;
254        f->buffer_hints = FF_BUFFER_HINTS_VALID |
255                          FF_BUFFER_HINTS_PRESERVE |
256                          FF_BUFFER_HINTS_REUSABLE;
257        if (avctx->reget_buffer(avctx, f)) {
258            av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
259            return -1;
260        }
261        /* skip frame */
262        if(buf_size == 8) {
263            f->pict_type = FF_P_TYPE;
264            f->key_frame = 0;
265            break;
266        }
267        f->pict_type = FF_I_TYPE;
268        f->key_frame = 1;
269        if ((AV_RL32(buf) != FPS_TAG)||(buf_size < (planes*1024 + 24))) {
270            av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
271            return -1;
272        }
273        for(i = 0; i < planes; i++) {
274            offs[i] = AV_RL32(buf + 4 + i * 4);
275            if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
276                av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
277                return -1;
278            }
279        }
280        offs[planes] = buf_size;
281        for(i = 0; i < planes; i++){
282            is_chroma = !!i;
283            s->tmpbuf = av_realloc(s->tmpbuf, offs[i + 1] - offs[i] - 1024 + FF_INPUT_BUFFER_PADDING_SIZE);
284            if(fraps2_decode_plane(s, f->data[i], f->linesize[i], avctx->width >> is_chroma,
285                    avctx->height >> is_chroma, buf + offs[i], offs[i + 1] - offs[i], is_chroma, 1) < 0) {
286                av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
287                return -1;
288            }
289        }
290        break;
291    case 3:
292    case 5:
293        /* Virtually the same as version 4, but is for RGB24 */
294        avctx->pix_fmt = PIX_FMT_BGR24;
295        planes = 3;
296        f->reference = 1;
297        f->buffer_hints = FF_BUFFER_HINTS_VALID |
298                          FF_BUFFER_HINTS_PRESERVE |
299                          FF_BUFFER_HINTS_REUSABLE;
300        if (avctx->reget_buffer(avctx, f)) {
301            av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
302            return -1;
303        }
304        /* skip frame */
305        if(buf_size == 8) {
306            f->pict_type = FF_P_TYPE;
307            f->key_frame = 0;
308            break;
309        }
310        f->pict_type = FF_I_TYPE;
311        f->key_frame = 1;
312        if ((AV_RL32(buf) != FPS_TAG)||(buf_size < (planes*1024 + 24))) {
313            av_log(avctx, AV_LOG_ERROR, "Fraps: error in data stream\n");
314            return -1;
315        }
316        for(i = 0; i < planes; i++) {
317            offs[i] = AV_RL32(buf + 4 + i * 4);
318            if(offs[i] >= buf_size || (i && offs[i] <= offs[i - 1] + 1024)) {
319                av_log(avctx, AV_LOG_ERROR, "Fraps: plane %i offset is out of bounds\n", i);
320                return -1;
321            }
322        }
323        offs[planes] = buf_size;
324        for(i = 0; i < planes; i++){
325            s->tmpbuf = av_realloc(s->tmpbuf, offs[i + 1] - offs[i] - 1024 + FF_INPUT_BUFFER_PADDING_SIZE);
326            if(fraps2_decode_plane(s, f->data[0] + i + (f->linesize[0] * (avctx->height - 1)), -f->linesize[0],
327                    avctx->width, avctx->height, buf + offs[i], offs[i + 1] - offs[i], 0, 3) < 0) {
328                av_log(avctx, AV_LOG_ERROR, "Error decoding plane %i\n", i);
329                return -1;
330            }
331        }
332        // convert pseudo-YUV into real RGB
333        for(j = 0; j < avctx->height; j++){
334            for(i = 0; i < avctx->width; i++){
335                f->data[0][0 + i*3 + j*f->linesize[0]] += f->data[0][1 + i*3 + j*f->linesize[0]];
336                f->data[0][2 + i*3 + j*f->linesize[0]] += f->data[0][1 + i*3 + j*f->linesize[0]];
337            }
338        }
339        break;
340    }
341
342    *frame = *f;
343    *data_size = sizeof(AVFrame);
344
345    return buf_size;
346}
347
348
349/**
350 * closes decoder
351 * @param avctx codec context
352 * @return 0 on success or negative if fails
353 */
354static av_cold int decode_end(AVCodecContext *avctx)
355{
356    FrapsContext *s = (FrapsContext*)avctx->priv_data;
357
358    if (s->frame.data[0])
359        avctx->release_buffer(avctx, &s->frame);
360
361    av_freep(&s->tmpbuf);
362    return 0;
363}
364
365
366AVCodec fraps_decoder = {
367    "fraps",
368    CODEC_TYPE_VIDEO,
369    CODEC_ID_FRAPS,
370    sizeof(FrapsContext),
371    decode_init,
372    NULL,
373    decode_end,
374    decode_frame,
375    CODEC_CAP_DR1,
376    .long_name = NULL_IF_CONFIG_SMALL("Fraps"),
377};
378