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bethsoftvideo.c
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1 /*
2  * Bethesda VID video decoder
3  * Copyright (C) 2007 Nicholas Tung
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 Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * @brief Bethesda Softworks VID Video Decoder
25  * @author Nicholas Tung [ntung (at. ntung com] (2007-03)
26  * @see http://wiki.multimedia.cx/index.php?title=Bethsoft_VID
27  * @see http://www.svatopluk.com/andux/docs/dfvid.html
28  */
29 
30 #include "libavutil/common.h"
31 #include "avcodec.h"
32 #include "bethsoftvideo.h"
33 #include "bytestream.h"
34 #include "internal.h"
35 
36 typedef struct BethsoftvidContext {
40 
42 {
43  BethsoftvidContext *vid = avctx->priv_data;
44  avctx->pix_fmt = AV_PIX_FMT_PAL8;
45 
46  vid->frame = av_frame_alloc();
47  if (!vid->frame)
48  return AVERROR(ENOMEM);
49 
50  return 0;
51 }
52 
54 {
55  uint32_t *palette = (uint32_t *)ctx->frame->data[1];
56  int a;
57 
58  if (bytestream2_get_bytes_left(&ctx->g) < 256*3)
59  return AVERROR_INVALIDDATA;
60 
61  for(a = 0; a < 256; a++){
62  palette[a] = 0xFFU << 24 | bytestream2_get_be24u(&ctx->g) * 4;
63  palette[a] |= palette[a] >> 6 & 0x30303;
64  }
65  ctx->frame->palette_has_changed = 1;
66  return 0;
67 }
68 
70  void *data, int *got_frame,
71  AVPacket *avpkt)
72 {
73  BethsoftvidContext * vid = avctx->priv_data;
74  char block_type;
75  uint8_t * dst;
77  int remaining = avctx->width; // number of bytes remaining on a line
78  int wrap_to_next_line;
79  int code, ret;
80  int yoffset;
81 
82  if ((ret = ff_reget_buffer(avctx, vid->frame)) < 0)
83  return ret;
84  wrap_to_next_line = vid->frame->linesize[0] - avctx->width;
85 
86  if (avpkt->side_data_elems > 0 &&
87  avpkt->side_data[0].type == AV_PKT_DATA_PALETTE) {
88  bytestream2_init(&vid->g, avpkt->side_data[0].data,
89  avpkt->side_data[0].size);
90  if ((ret = set_palette(vid)) < 0)
91  return ret;
92  }
93 
94  bytestream2_init(&vid->g, avpkt->data, avpkt->size);
95  dst = vid->frame->data[0];
96  frame_end = vid->frame->data[0] + vid->frame->linesize[0] * avctx->height;
97 
98  switch(block_type = bytestream2_get_byte(&vid->g)){
99  case PALETTE_BLOCK: {
100  *got_frame = 0;
101  if ((ret = set_palette(vid)) < 0) {
102  av_log(avctx, AV_LOG_ERROR, "error reading palette\n");
103  return ret;
104  }
105  return bytestream2_tell(&vid->g);
106  }
107  case VIDEO_YOFF_P_FRAME:
108  yoffset = bytestream2_get_le16(&vid->g);
109  if(yoffset >= avctx->height)
110  return AVERROR_INVALIDDATA;
111  dst += vid->frame->linesize[0] * yoffset;
112  }
113 
114  // main code
115  while((code = bytestream2_get_byte(&vid->g))){
116  int length = code & 0x7f;
117 
118  // copy any bytes starting at the current position, and ending at the frame width
119  while(length > remaining){
120  if(code < 0x80)
121  bytestream2_get_buffer(&vid->g, dst, remaining);
122  else if(block_type == VIDEO_I_FRAME)
123  memset(dst, bytestream2_peek_byte(&vid->g), remaining);
124  length -= remaining; // decrement the number of bytes to be copied
125  dst += remaining + wrap_to_next_line; // skip over extra bytes at end of frame
126  remaining = avctx->width;
127  if(dst == frame_end)
128  goto end;
129  }
130 
131  // copy any remaining bytes after / if line overflows
132  if(code < 0x80)
133  bytestream2_get_buffer(&vid->g, dst, length);
134  else if(block_type == VIDEO_I_FRAME)
135  memset(dst, bytestream2_get_byte(&vid->g), length);
136  remaining -= length;
137  dst += length;
138  }
139  end:
140 
141  if ((ret = av_frame_ref(data, vid->frame)) < 0)
142  return ret;
143 
144  *got_frame = 1;
145 
146  return avpkt->size;
147 }
148 
150 {
151  BethsoftvidContext * vid = avctx->priv_data;
152  av_frame_free(&vid->frame);
153  return 0;
154 }
155 
157  .name = "bethsoftvid",
158  .long_name = NULL_IF_CONFIG_SMALL("Bethesda VID video"),
159  .type = AVMEDIA_TYPE_VIDEO,
161  .priv_data_size = sizeof(BethsoftvidContext),
163  .close = bethsoftvid_decode_end,
165  .capabilities = AV_CODEC_CAP_DR1,
166 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:180
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
AVFormatContext * ctx
Definition: movenc-test.c:48
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1578
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1870
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
AVCodec.
Definition: avcodec.h:3535
AVCodec ff_bethsoftvid_decoder
uint8_t
#define av_cold
Definition: attributes.h:82
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:140
8 bit with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:73
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:374
uint8_t * data
Definition: avcodec.h:1577
uint8_t * data
Definition: avcodec.h:1521
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:153
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:263
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
enum AVPacketSideDataType type
Definition: avcodec.h:1523
GLsizei GLsizei * length
Definition: opengl_enc.c:115
const char * name
Name of the codec implementation.
Definition: avcodec.h:3542
int side_data_elems
Definition: avcodec.h:1589
static int bethsoftvid_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: bethsoftvideo.c:69
static void frame_end(MpegEncContext *s)
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
Identical in function to av_frame_make_writable(), except it uses ff_get_buffer() to allocate the buf...
Definition: utils.c:977
int width
picture width / height.
Definition: avcodec.h:1829
static int set_palette(BethsoftvidContext *ctx)
Definition: bethsoftvideo.c:53
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:188
Libavcodec external API header.
static av_cold int bethsoftvid_decode_end(AVCodecContext *avctx)
static av_cold int bethsoftvid_decode_init(AVCodecContext *avctx)
Definition: bethsoftvideo.c:41
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:211
main external API structure.
Definition: avcodec.h:1642
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:324
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:194
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:722
int palette
Definition: v4l.c:61
AVPacketSideData * side_data
Additional packet data that can be provided by the container.
Definition: avcodec.h:1588
common internal api header.
common internal and external API header
if(ret< 0)
Definition: vf_mcdeint.c:282
void * priv_data
Definition: avcodec.h:1684
This structure stores compressed data.
Definition: avcodec.h:1554
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:953
GetByteContext g
Definition: bethsoftvideo.c:38