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.
41 #include "libavutil/internal.h"
43 #include "bytestream.h"
46 typedef struct RpzaContext {
48 AVCodecContext *avctx;
54 #define ADVANCE_BLOCK() \
57 if (pixel_ptr >= width) \
60 row_ptr += stride * 4; \
63 if (total_blocks < 0) \
65 av_log(s->avctx, AV_LOG_ERROR, "warning: block counter just went negative (this should not happen)\n"); \
70 static void rpza_decode_stream(RpzaContext *s)
72 int width = s->avctx->width;
73 int stride = s->frame->linesize[0] / 2;
74 int row_inc = stride - 4;
78 unsigned short colorA = 0, colorB;
79 unsigned short color4[4];
80 unsigned char index, idx;
81 unsigned short ta, tb;
82 unsigned short *pixels = (unsigned short *)s->frame->data[0];
90 /* First byte is always 0xe1. Warn if it's different */
91 if (bytestream2_peek_byte(&s->gb) != 0xe1)
92 av_log(s->avctx, AV_LOG_ERROR, "First chunk byte is 0x%02x instead of 0xe1\n",
93 bytestream2_peek_byte(&s->gb));
95 /* Get chunk size, ingnoring first byte */
96 chunk_size = bytestream2_get_be32(&s->gb) & 0x00FFFFFF;
98 /* If length mismatch use size from MOV file and try to decode anyway */
99 if (chunk_size != bytestream2_get_bytes_left(&s->gb) - 4)
100 av_log(s->avctx, AV_LOG_WARNING, "MOV chunk size != encoded chunk size\n");
102 /* Number of 4x4 blocks in frame. */
103 total_blocks = ((s->avctx->width + 3) / 4) * ((s->avctx->height + 3) / 4);
105 /* Process chunk data */
106 while (bytestream2_get_bytes_left(&s->gb)) {
107 opcode = bytestream2_get_byte(&s->gb); /* Get opcode */
109 n_blocks = (opcode & 0x1f) + 1; /* Extract block counter from opcode */
111 /* If opcode MSbit is 0, we need more data to decide what to do */
112 if ((opcode & 0x80) == 0) {
113 colorA = (opcode << 8) | bytestream2_get_byte(&s->gb);
115 if ((bytestream2_peek_byte(&s->gb) & 0x80) != 0) {
116 /* Must behave as opcode 110xxxxx, using colorA computed
117 * above. Use fake opcode 0x20 to enter switch block at
124 switch (opcode & 0xe0) {
133 /* Fill blocks with one color */
135 colorA = bytestream2_get_be16(&s->gb);
138 block_ptr = row_ptr + pixel_ptr;
139 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
140 for (pixel_x = 0; pixel_x < 4; pixel_x++){
141 pixels[block_ptr] = colorA;
144 block_ptr += row_inc;
149 /* Fill blocks with 4 colors */
151 colorA = bytestream2_get_be16(&s->gb);
153 colorB = bytestream2_get_be16(&s->gb);
155 /* sort out the colors */
162 ta = (colorA >> 10) & 0x1F;
163 tb = (colorB >> 10) & 0x1F;
164 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 10;
165 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 10;
167 /* green components */
168 ta = (colorA >> 5) & 0x1F;
169 tb = (colorB >> 5) & 0x1F;
170 color4[1] |= ((11 * ta + 21 * tb) >> 5) << 5;
171 color4[2] |= ((21 * ta + 11 * tb) >> 5) << 5;
173 /* blue components */
176 color4[1] |= ((11 * ta + 21 * tb) >> 5);
177 color4[2] |= ((21 * ta + 11 * tb) >> 5);
179 if (bytestream2_get_bytes_left(&s->gb) < n_blocks * 4)
183 block_ptr = row_ptr + pixel_ptr;
184 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
185 index = bytestream2_get_byteu(&s->gb);
186 for (pixel_x = 0; pixel_x < 4; pixel_x++){
187 idx = (index >> (2 * (3 - pixel_x))) & 0x03;
188 pixels[block_ptr] = color4[idx];
191 block_ptr += row_inc;
196 /* Fill block with 16 colors */
198 if (bytestream2_get_bytes_left(&s->gb) < 30)
201 block_ptr = row_ptr + pixel_ptr;
202 for (pixel_y = 0; pixel_y < 4; pixel_y++) {
203 for (pixel_x = 0; pixel_x < 4; pixel_x++){
204 /* We already have color of upper left pixel */
205 if ((pixel_y != 0) || (pixel_x != 0))
206 colorA = bytestream2_get_be16u(&s->gb);
207 pixels[block_ptr] = colorA;
210 block_ptr += row_inc;
216 av_log(s->avctx, AV_LOG_ERROR, "Unknown opcode %d in rpza chunk."
217 " Skip remaining %d bytes of chunk data.\n", opcode,
218 bytestream2_get_bytes_left(&s->gb));
220 } /* Opcode switch */
224 static av_cold int rpza_decode_init(AVCodecContext *avctx)
226 RpzaContext *s = avctx->priv_data;
229 avctx->pix_fmt = AV_PIX_FMT_RGB555;
231 s->frame = av_frame_alloc();
233 return AVERROR(ENOMEM);
238 static int rpza_decode_frame(AVCodecContext *avctx,
239 void *data, int *got_frame,
242 RpzaContext *s = avctx->priv_data;
245 bytestream2_init(&s->gb, avpkt->data, avpkt->size);
247 if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
250 rpza_decode_stream(s);
252 if ((ret = av_frame_ref(data, s->frame)) < 0)
257 /* always report that the buffer was completely consumed */
261 static av_cold int rpza_decode_end(AVCodecContext *avctx)
263 RpzaContext *s = avctx->priv_data;
265 av_frame_free(&s->frame);
270 AVCodec ff_rpza_decoder = {
272 .long_name = NULL_IF_CONFIG_SMALL("QuickTime video (RPZA)"),
273 .type = AVMEDIA_TYPE_VIDEO,
274 .id = AV_CODEC_ID_RPZA,
275 .priv_data_size = sizeof(RpzaContext),
276 .init = rpza_decode_init,
277 .close = rpza_decode_end,
278 .decode = rpza_decode_frame,
279 .capabilities = CODEC_CAP_DR1,