* American Laser Games MM Video Decoder
* Copyright (c) 2006,2008 Peter Ross
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
- * @file mm.c
+ * @file
* American Laser Games MM Video Decoder
- * by Peter Ross (suxen_drol at hotmail dot com)
+ * by Peter Ross (pross@xvid.org)
*
* The MM format was used by IBM-PC ports of ALG's "arcade shooter" games,
* including Mad Dog McCree and Crime Patrol.
* http://wiki.multimedia.cx/index.php?title=American_Laser_Games_MM
*/
+#include "libavutil/intreadwrite.h"
#include "avcodec.h"
+#include "bytestream.h"
+#include "internal.h"
#define MM_PREAMBLE_SIZE 6
typedef struct MmContext {
AVCodecContext *avctx;
- AVFrame frame;
+ AVFrame *frame;
int palette[AVPALETTE_COUNT];
+ GetByteContext gb;
} MmContext;
static av_cold int mm_decode_init(AVCodecContext *avctx)
s->avctx = avctx;
- avctx->pix_fmt = PIX_FMT_PAL8;
+ avctx->pix_fmt = AV_PIX_FMT_PAL8;
- if (avcodec_check_dimensions(avctx, avctx->width, avctx->height))
- return -1;
-
- s->frame.reference = 1;
- if (avctx->get_buffer(avctx, &s->frame)) {
- av_log(s->avctx, AV_LOG_ERROR, "mmvideo: get_buffer() failed\n");
- return -1;
- }
+ s->frame = av_frame_alloc();
+ if (!s->frame)
+ return AVERROR(ENOMEM);
return 0;
}
-static void mm_decode_pal(MmContext *s, const uint8_t *buf, const uint8_t *buf_end)
+static int mm_decode_pal(MmContext *s)
{
int i;
- buf += 4;
- for (i=0; i<128 && buf+2<buf_end; i++) {
- s->palette[i] = AV_RB24(buf);
+
+ bytestream2_skip(&s->gb, 4);
+ for (i = 0; i < 128; i++) {
+ s->palette[i] = bytestream2_get_be24(&s->gb);
s->palette[i+128] = s->palette[i]<<2;
- buf += 3;
}
+
+ return 0;
}
-static void mm_decode_intra(MmContext * s, int half_horiz, int half_vert, const uint8_t *buf, int buf_size)
+/**
+ * @param half_horiz Half horizontal resolution (0 or 1)
+ * @param half_vert Half vertical resolution (0 or 1)
+ */
+static int mm_decode_intra(MmContext * s, int half_horiz, int half_vert)
{
- int i, x, y;
- i=0; x=0; y=0;
+ int x = 0, y = 0;
- while(i<buf_size) {
+ while (bytestream2_get_bytes_left(&s->gb) > 0) {
int run_length, color;
- if (buf[i] & 0x80) {
+ if (y >= s->avctx->height)
+ return 0;
+
+ color = bytestream2_get_byte(&s->gb);
+ if (color & 0x80) {
run_length = 1;
- color = buf[i];
- i++;
}else{
- run_length = (buf[i] & 0x7f) + 2;
- color = buf[i+1];
- i+=2;
+ run_length = (color & 0x7f) + 2;
+ color = bytestream2_get_byte(&s->gb);
}
if (half_horiz)
run_length *=2;
if (color) {
- memset(s->frame.data[0] + y*s->frame.linesize[0] + x, color, run_length);
+ memset(s->frame->data[0] + y*s->frame->linesize[0] + x, color, run_length);
if (half_vert)
- memset(s->frame.data[0] + (y+1)*s->frame.linesize[0] + x, color, run_length);
+ memset(s->frame->data[0] + (y+1)*s->frame->linesize[0] + x, color, run_length);
}
x+= run_length;
if (x >= s->avctx->width) {
x=0;
- y += half_vert ? 2 : 1;
+ y += 1 + half_vert;
}
}
+
+ return 0;
}
-static void mm_decode_inter(MmContext * s, int half_horiz, int half_vert, const uint8_t *buf, int buf_size)
+/*
+ * @param half_horiz Half horizontal resolution (0 or 1)
+ * @param half_vert Half vertical resolution (0 or 1)
+ */
+static int mm_decode_inter(MmContext * s, int half_horiz, int half_vert)
{
- const int data_ptr = 2 + AV_RL16(&buf[0]);
- int d, r, y;
- d = data_ptr; r = 2; y = 0;
+ int data_off = bytestream2_get_le16(&s->gb);
+ int y = 0;
+ GetByteContext data_ptr;
+
+ if (bytestream2_get_bytes_left(&s->gb) < data_off)
+ return AVERROR_INVALIDDATA;
- while(r < data_ptr) {
+ bytestream2_init(&data_ptr, s->gb.buffer + data_off, bytestream2_get_bytes_left(&s->gb) - data_off);
+ while (s->gb.buffer < data_ptr.buffer_start) {
int i, j;
- int length = buf[r] & 0x7f;
- int x = buf[r+1] + ((buf[r] & 0x80) << 1);
- r += 2;
+ int length = bytestream2_get_byte(&s->gb);
+ int x = bytestream2_get_byte(&s->gb) + ((length & 0x80) << 1);
+ length &= 0x7F;
if (length==0) {
y += x;
continue;
}
+ if (y + half_vert >= s->avctx->height)
+ return 0;
+
for(i=0; i<length; i++) {
+ int replace_array = bytestream2_get_byte(&s->gb);
for(j=0; j<8; j++) {
- int replace = (buf[r+i] >> (7-j)) & 1;
+ int replace = (replace_array >> (7-j)) & 1;
+ if (x + half_horiz >= s->avctx->width)
+ return AVERROR_INVALIDDATA;
if (replace) {
- int color = buf[d];
- s->frame.data[0][y*s->frame.linesize[0] + x] = color;
+ int color = bytestream2_get_byte(&data_ptr);
+ s->frame->data[0][y*s->frame->linesize[0] + x] = color;
if (half_horiz)
- s->frame.data[0][y*s->frame.linesize[0] + x + 1] = color;
+ s->frame->data[0][y*s->frame->linesize[0] + x + 1] = color;
if (half_vert) {
- s->frame.data[0][(y+1)*s->frame.linesize[0] + x] = color;
+ s->frame->data[0][(y+1)*s->frame->linesize[0] + x] = color;
if (half_horiz)
- s->frame.data[0][(y+1)*s->frame.linesize[0] + x + 1] = color;
+ s->frame->data[0][(y+1)*s->frame->linesize[0] + x + 1] = color;
}
- d++;
}
- x += half_horiz ? 2 : 1;
+ x += 1 + half_horiz;
}
}
- r += length;
- y += half_vert ? 2 : 1;
+ y += 1 + half_vert;
}
+
+ return 0;
}
static int mm_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- const uint8_t *buf, int buf_size)
+ void *data, int *got_frame,
+ AVPacket *avpkt)
{
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
MmContext *s = avctx->priv_data;
- const uint8_t *buf_end = buf+buf_size;
- int type;
+ int type, res;
+ if (buf_size < MM_PREAMBLE_SIZE)
+ return AVERROR_INVALIDDATA;
type = AV_RL16(&buf[0]);
buf += MM_PREAMBLE_SIZE;
buf_size -= MM_PREAMBLE_SIZE;
+ bytestream2_init(&s->gb, buf, buf_size);
+
+ if ((res = ff_reget_buffer(avctx, s->frame)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
+ return res;
+ }
switch(type) {
- case MM_TYPE_PALETTE : mm_decode_pal(s, buf, buf_end); return buf_size;
- case MM_TYPE_INTRA : mm_decode_intra(s, 0, 0, buf, buf_size); break;
- case MM_TYPE_INTRA_HH : mm_decode_intra(s, 1, 0, buf, buf_size); break;
- case MM_TYPE_INTRA_HHV : mm_decode_intra(s, 1, 1, buf, buf_size); break;
- case MM_TYPE_INTER : mm_decode_inter(s, 0, 0, buf, buf_size); break;
- case MM_TYPE_INTER_HH : mm_decode_inter(s, 1, 0, buf, buf_size); break;
- case MM_TYPE_INTER_HHV : mm_decode_inter(s, 1, 1, buf, buf_size); break;
- default :
- return -1;
+ case MM_TYPE_PALETTE : res = mm_decode_pal(s); return buf_size;
+ case MM_TYPE_INTRA : res = mm_decode_intra(s, 0, 0); break;
+ case MM_TYPE_INTRA_HH : res = mm_decode_intra(s, 1, 0); break;
+ case MM_TYPE_INTRA_HHV : res = mm_decode_intra(s, 1, 1); break;
+ case MM_TYPE_INTER : res = mm_decode_inter(s, 0, 0); break;
+ case MM_TYPE_INTER_HH : res = mm_decode_inter(s, 1, 0); break;
+ case MM_TYPE_INTER_HHV : res = mm_decode_inter(s, 1, 1); break;
+ default:
+ res = AVERROR_INVALIDDATA;
+ break;
}
+ if (res < 0)
+ return res;
+
+ memcpy(s->frame->data[1], s->palette, AVPALETTE_SIZE);
- memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE);
+ if ((res = av_frame_ref(data, s->frame)) < 0)
+ return res;
- *data_size = sizeof(AVFrame);
- *(AVFrame*)data = s->frame;
+ *got_frame = 1;
return buf_size;
}
{
MmContext *s = avctx->priv_data;
- if(s->frame.data[0])
- avctx->release_buffer(avctx, &s->frame);
+ av_frame_free(&s->frame);
return 0;
}
-AVCodec mmvideo_decoder = {
- "mmvideo",
- CODEC_TYPE_VIDEO,
- CODEC_ID_MMVIDEO,
- sizeof(MmContext),
- mm_decode_init,
- NULL,
- mm_decode_end,
- mm_decode_frame,
- CODEC_CAP_DR1,
- .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM Video"),
+AVCodec ff_mmvideo_decoder = {
+ .name = "mmvideo",
+ .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM Video"),
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_MMVIDEO,
+ .priv_data_size = sizeof(MmContext),
+ .init = mm_decode_init,
+ .close = mm_decode_end,
+ .decode = mm_decode_frame,
+ .capabilities = CODEC_CAP_DR1,
};