tmv.c
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1 /*
2  * 8088flex TMV video decoder
3  * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
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 
29 #include <string.h>
30 
31 #include "avcodec.h"
32 #include "internal.h"
33 #include "libavutil/internal.h"
34 
35 #include "cga_data.h"
36 
37 typedef struct TMVContext {
39 } TMVContext;
40 
41 static int tmv_decode_frame(AVCodecContext *avctx, void *data,
42  int *got_frame, AVPacket *avpkt)
43 {
44  TMVContext *tmv = avctx->priv_data;
45  const uint8_t *src = avpkt->data;
46  uint8_t *dst;
47  unsigned char_cols = avctx->width >> 3;
48  unsigned char_rows = avctx->height >> 3;
49  unsigned x, y, fg, bg, c;
50 
51  if (tmv->pic.data[0])
52  avctx->release_buffer(avctx, &tmv->pic);
53 
54  if (ff_get_buffer(avctx, &tmv->pic) < 0) {
55  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
56  return -1;
57  }
58 
59  if (avpkt->size < 2*char_rows*char_cols) {
60  av_log(avctx, AV_LOG_ERROR,
61  "Input buffer too small, truncated sample?\n");
62  *got_frame = 0;
63  return -1;
64  }
65 
67  tmv->pic.key_frame = 1;
68  dst = tmv->pic.data[0];
69 
70  tmv->pic.palette_has_changed = 1;
71  memcpy(tmv->pic.data[1], ff_cga_palette, 16 * 4);
72 
73  for (y = 0; y < char_rows; y++) {
74  for (x = 0; x < char_cols; x++) {
75  c = *src++;
76  bg = *src >> 4;
77  fg = *src++ & 0xF;
78  ff_draw_pc_font(dst + x * 8, tmv->pic.linesize[0],
79  ff_cga_font, 8, c, fg, bg);
80  }
81  dst += tmv->pic.linesize[0] * 8;
82  }
83 
84  *got_frame = 1;
85  *(AVFrame *)data = tmv->pic;
86  return avpkt->size;
87 }
88 
90 {
91  avctx->pix_fmt = AV_PIX_FMT_PAL8;
92  return 0;
93 }
94 
96 {
97  TMVContext *tmv = avctx->priv_data;
98 
99  if (tmv->pic.data[0])
100  avctx->release_buffer(avctx, &tmv->pic);
101 
102  return 0;
103 }
104 
106  .name = "tmv",
107  .type = AVMEDIA_TYPE_VIDEO,
108  .id = AV_CODEC_ID_TMV,
109  .priv_data_size = sizeof(TMVContext),
113  .capabilities = CODEC_CAP_DR1,
114  .long_name = NULL_IF_CONFIG_SMALL("8088flex TMV"),
115 };
const uint8_t ff_cga_font[2048]
Definition: cga_data.c:29
This structure describes decoded (raw) audio or video data.
Definition: avcodec.h:989
Definition: tmv.c:37
void(* release_buffer)(struct AVCodecContext *c, AVFrame *pic)
Called to release buffers which were allocated with get_buffer.
Definition: avcodec.h:2259
int size
Definition: avcodec.h:916
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1533
AVCodec.
Definition: avcodec.h:2960
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:228
uint8_t
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:76
const char data[16]
Definition: mxf.c:66
uint8_t * data
Definition: avcodec.h:915
CGA/EGA/VGA ROM data.
static int init(AVCodecParserContext *s)
Definition: h264_parser.c:335
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:88
static int tmv_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: tmv.c:41
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:146
const char * name
Name of the codec implementation.
Definition: avcodec.h:2967
common internal API header
AVCodec ff_tmv_decoder
Definition: tmv.c:105
enum AVPictureType pict_type
Picture type of the frame, see ?_TYPE below.
Definition: avcodec.h:1065
int width
picture width / height.
Definition: avcodec.h:1508
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame)
Get a buffer for a frame.
Definition: utils.c:464
static av_cold int tmv_decode_close(AVCodecContext *avctx)
Definition: tmv.c:95
void ff_draw_pc_font(uint8_t *dst, int linesize, const uint8_t *font, int font_height, int ch, int fg, int bg)
Draw CGA/EGA/VGA font to 8-bit pixel buffer.
Definition: cga_data.c:435
external API header
struct TMVContext TMVContext
int linesize[AV_NUM_DATA_POINTERS]
Size, in bytes, of the data for each picture/channel plane.
Definition: avcodec.h:1008
main external API structure.
Definition: avcodec.h:1339
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:326
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: avcodec.h:1246
const uint32_t ff_cga_palette[16]
Definition: cga_data.c:419
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: avcodec.h:997
common internal api header.
AVFrame pic
Definition: tmv.c:38
void * priv_data
Definition: avcodec.h:1382
int key_frame
1 -> keyframe, 0-> not
Definition: avcodec.h:1058
This structure stores compressed data.
Definition: avcodec.h:898
static av_cold int tmv_decode_init(AVCodecContext *avctx)
Definition: tmv.c:89