Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
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] = bytestream2_get_be24u(&ctx->g) * 4;
63  }
64  ctx->frame->palette_has_changed = 1;
65  return 0;
66 }
67 
69  void *data, int *got_frame,
70  AVPacket *avpkt)
71 {
72  BethsoftvidContext * vid = avctx->priv_data;
73  char block_type;
74  uint8_t * dst;
76  int remaining = avctx->width; // number of bytes remaining on a line
77  int wrap_to_next_line;
78  int code, ret;
79  int yoffset;
80 
81  if ((ret = ff_reget_buffer(avctx, vid->frame)) < 0) {
82  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
83  return ret;
84  }
85  wrap_to_next_line = vid->frame->linesize[0] - avctx->width;
86 
87  if (avpkt->side_data_elems > 0 &&
88  avpkt->side_data[0].type == AV_PKT_DATA_PALETTE) {
89  bytestream2_init(&vid->g, avpkt->side_data[0].data,
90  avpkt->side_data[0].size);
91  if ((ret = set_palette(vid)) < 0)
92  return ret;
93  }
94 
95  bytestream2_init(&vid->g, avpkt->data, avpkt->size);
96  dst = vid->frame->data[0];
97  frame_end = vid->frame->data[0] + vid->frame->linesize[0] * avctx->height;
98 
99  switch(block_type = bytestream2_get_byte(&vid->g)){
100  case PALETTE_BLOCK: {
101  *got_frame = 0;
102  if ((ret = set_palette(vid)) < 0) {
103  av_log(avctx, AV_LOG_ERROR, "error reading palette\n");
104  return ret;
105  }
106  return bytestream2_tell(&vid->g);
107  }
108  case VIDEO_YOFF_P_FRAME:
109  yoffset = bytestream2_get_le16(&vid->g);
110  if(yoffset >= avctx->height)
111  return AVERROR_INVALIDDATA;
112  dst += vid->frame->linesize[0] * yoffset;
113  }
114 
115  // main code
116  while((code = bytestream2_get_byte(&vid->g))){
117  int length = code & 0x7f;
118 
119  // copy any bytes starting at the current position, and ending at the frame width
120  while(length > remaining){
121  if(code < 0x80)
122  bytestream2_get_buffer(&vid->g, dst, remaining);
123  else if(block_type == VIDEO_I_FRAME)
124  memset(dst, bytestream2_peek_byte(&vid->g), remaining);
125  length -= remaining; // decrement the number of bytes to be copied
126  dst += remaining + wrap_to_next_line; // skip over extra bytes at end of frame
127  remaining = avctx->width;
128  if(dst == frame_end)
129  goto end;
130  }
131 
132  // copy any remaining bytes after / if line overflows
133  if(code < 0x80)
134  bytestream2_get_buffer(&vid->g, dst, length);
135  else if(block_type == VIDEO_I_FRAME)
136  memset(dst, bytestream2_get_byte(&vid->g), length);
137  remaining -= length;
138  dst += length;
139  }
140  end:
141 
142  if ((ret = av_frame_ref(data, vid->frame)) < 0)
143  return ret;
144 
145  *got_frame = 1;
146 
147  return avpkt->size;
148 }
149 
151 {
152  BethsoftvidContext * vid = avctx->priv_data;
153  av_frame_free(&vid->frame);
154  return 0;
155 }
156 
158  .name = "bethsoftvid",
159  .long_name = NULL_IF_CONFIG_SMALL("Bethesda VID video"),
160  .type = AVMEDIA_TYPE_VIDEO,
162  .priv_data_size = sizeof(BethsoftvidContext),
166  .capabilities = CODEC_CAP_DR1,
167 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
int size
Definition: avcodec.h:974
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1254
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:130
AVCodec.
Definition: avcodec.h:2796
AVCodec ff_bethsoftvid_decoder
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:275
uint8_t
#define av_cold
Definition: attributes.h:66
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:57
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:76
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:188
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:684
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:973
uint8_t * data
Definition: avcodec.h:923
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
#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:69
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:258
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:149
enum AVPacketSideDataType type
Definition: avcodec.h:925
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:168
const char * name
Name of the codec implementation.
Definition: avcodec.h:2803
int side_data_elems
Definition: avcodec.h:985
static int bethsoftvid_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: bethsoftvideo.c:68
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:808
int width
picture width / height.
Definition: avcodec.h:1224
static int set_palette(BethsoftvidContext *ctx)
Definition: bethsoftvideo.c:53
if(ac->has_optimized_func)
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:183
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:153
main external API structure.
Definition: avcodec.h:1050
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:330
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
AVPacketSideData * side_data
Additional packet data that can be provided by the container.
Definition: avcodec.h:984
common internal api header.
common internal and external API header
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
void * priv_data
Definition: avcodec.h:1092
This structure stores compressed data.
Definition: avcodec.h:950
GetByteContext g
Definition: bethsoftvideo.c:38