2 * Quicktime Video (RPZA) Video Decoder
3 * Copyright (c) 2003 The FFmpeg Project
5 * This file is part of FFmpeg.
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.
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.
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
24 * QT RPZA Video Decoder by Roberto Togni
25 * For more information about the RPZA format, visit:
26 * http://www.pcisys.net/~melanson/codecs/
28 * The RPZA decoder outputs RGB555 colorspace data.
30 * Note that this decoder reads big endian RGB555 pixel values from the
31 * bytestream, arranges them in the host's endian order, and outputs
32 * them to the final rendered map in the same host endian order. This is
33 * intended behavior as the libavcodec documentation states that RGB555
34 * pixels shall be stored in native CPU endianness.
42 #include "libavutil/internal.h"
44 #include "bytestream.h"
47 typedef struct RpzaContext
{
49 AVCodecContext
*avctx
;
55 #define ADVANCE_BLOCK() \
58 if (pixel_ptr >= width) \
61 row_ptr += stride * 4; \
64 if (total_blocks < 0) \
66 av_log(s->avctx, AV_LOG_ERROR, "warning: block counter just went negative (this should not happen)\n"); \
71 static void rpza_decode_stream(RpzaContext
*s
)
73 int width
= s
->avctx
->width
;
74 int stride
= s
->frame
->linesize
[0] / 2;
75 int row_inc
= stride
- 4;
77 uint16_t colorA
= 0, colorB
;
80 uint16_t *pixels
= (uint16_t *)s
->frame
->data
[0];
88 /* First byte is always 0xe1. Warn if it's different */
89 if (bytestream2_peek_byte(&s
->gb
) != 0xe1)
90 av_log(s
->avctx
, AV_LOG_ERROR
, "First chunk byte is 0x%02x instead of 0xe1\n",
91 bytestream2_peek_byte(&s
->gb
));
93 /* Get chunk size, ingnoring first byte */
94 chunk_size
= bytestream2_get_be32(&s
->gb
) & 0x00FFFFFF;
96 /* If length mismatch use size from MOV file and try to decode anyway */
97 if (chunk_size
!= bytestream2_get_bytes_left(&s
->gb
) + 4)
98 av_log(s
->avctx
, AV_LOG_WARNING
,
99 "MOV chunk size %d != encoded chunk size %d\n",
101 bytestream2_get_bytes_left(&s
->gb
) + 4
104 /* Number of 4x4 blocks in frame. */
105 total_blocks
= ((s
->avctx
->width
+ 3) / 4) * ((s
->avctx
->height
+ 3) / 4);
107 /* Process chunk data */
108 while (bytestream2_get_bytes_left(&s
->gb
)) {
109 uint8_t opcode
= bytestream2_get_byte(&s
->gb
); /* Get opcode */
111 int n_blocks
= (opcode
& 0x1f) + 1; /* Extract block counter from opcode */
113 /* If opcode MSbit is 0, we need more data to decide what to do */
114 if ((opcode
& 0x80) == 0) {
115 colorA
= (opcode
<< 8) | bytestream2_get_byte(&s
->gb
);
117 if ((bytestream2_peek_byte(&s
->gb
) & 0x80) != 0) {
118 /* Must behave as opcode 110xxxxx, using colorA computed
119 * above. Use fake opcode 0x20 to enter switch block at
126 n_blocks
= FFMIN(n_blocks
, total_blocks
);
128 switch (opcode
& 0xe0) {
137 /* Fill blocks with one color */
139 colorA
= bytestream2_get_be16(&s
->gb
);
142 block_ptr
= row_ptr
+ pixel_ptr
;
143 for (pixel_y
= 0; pixel_y
< 4; pixel_y
++) {
144 for (pixel_x
= 0; pixel_x
< 4; pixel_x
++){
145 pixels
[block_ptr
] = colorA
;
148 block_ptr
+= row_inc
;
153 /* Fill blocks with 4 colors */
155 colorA
= bytestream2_get_be16(&s
->gb
);
157 colorB
= bytestream2_get_be16(&s
->gb
);
159 /* sort out the colors */
166 ta
= (colorA
>> 10) & 0x1F;
167 tb
= (colorB
>> 10) & 0x1F;
168 color4
[1] |= ((11 * ta
+ 21 * tb
) >> 5) << 10;
169 color4
[2] |= ((21 * ta
+ 11 * tb
) >> 5) << 10;
171 /* green components */
172 ta
= (colorA
>> 5) & 0x1F;
173 tb
= (colorB
>> 5) & 0x1F;
174 color4
[1] |= ((11 * ta
+ 21 * tb
) >> 5) << 5;
175 color4
[2] |= ((21 * ta
+ 11 * tb
) >> 5) << 5;
177 /* blue components */
180 color4
[1] |= ((11 * ta
+ 21 * tb
) >> 5);
181 color4
[2] |= ((21 * ta
+ 11 * tb
) >> 5);
183 if (bytestream2_get_bytes_left(&s
->gb
) < n_blocks
* 4)
187 block_ptr
= row_ptr
+ pixel_ptr
;
188 for (pixel_y
= 0; pixel_y
< 4; pixel_y
++) {
189 uint8_t index
= bytestream2_get_byteu(&s
->gb
);
190 for (pixel_x
= 0; pixel_x
< 4; pixel_x
++){
191 uint8_t idx
= (index
>> (2 * (3 - pixel_x
))) & 0x03;
192 pixels
[block_ptr
] = color4
[idx
];
195 block_ptr
+= row_inc
;
200 /* Fill block with 16 colors */
202 if (bytestream2_get_bytes_left(&s
->gb
) < 30)
205 block_ptr
= row_ptr
+ pixel_ptr
;
206 for (pixel_y
= 0; pixel_y
< 4; pixel_y
++) {
207 for (pixel_x
= 0; pixel_x
< 4; pixel_x
++){
208 /* We already have color of upper left pixel */
209 if ((pixel_y
!= 0) || (pixel_x
!= 0))
210 colorA
= bytestream2_get_be16u(&s
->gb
);
211 pixels
[block_ptr
] = colorA
;
214 block_ptr
+= row_inc
;
220 av_log(s
->avctx
, AV_LOG_ERROR
, "Unknown opcode %d in rpza chunk."
221 " Skip remaining %d bytes of chunk data.\n", opcode
,
222 bytestream2_get_bytes_left(&s
->gb
));
224 } /* Opcode switch */
228 static av_cold
int rpza_decode_init(AVCodecContext
*avctx
)
230 RpzaContext
*s
= avctx
->priv_data
;
233 avctx
->pix_fmt
= AV_PIX_FMT_RGB555
;
235 s
->frame
= av_frame_alloc();
237 return AVERROR(ENOMEM
);
242 static int rpza_decode_frame(AVCodecContext
*avctx
,
243 void *data
, int *got_frame
,
246 RpzaContext
*s
= avctx
->priv_data
;
249 bytestream2_init(&s
->gb
, avpkt
->data
, avpkt
->size
);
251 if ((ret
= ff_reget_buffer(avctx
, s
->frame
)) < 0)
254 rpza_decode_stream(s
);
256 if ((ret
= av_frame_ref(data
, s
->frame
)) < 0)
261 /* always report that the buffer was completely consumed */
265 static av_cold
int rpza_decode_end(AVCodecContext
*avctx
)
267 RpzaContext
*s
= avctx
->priv_data
;
269 av_frame_free(&s
->frame
);
274 AVCodec ff_rpza_decoder
= {
276 .long_name
= NULL_IF_CONFIG_SMALL("QuickTime video (RPZA)"),
277 .type
= AVMEDIA_TYPE_VIDEO
,
278 .id
= AV_CODEC_ID_RPZA
,
279 .priv_data_size
= sizeof(RpzaContext
),
280 .init
= rpza_decode_init
,
281 .close
= rpza_decode_end
,
282 .decode
= rpza_decode_frame
,
283 .capabilities
= CODEC_CAP_DR1
,