static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { JvContext *s = avctx->priv_data; const uint8_t *buf = avpkt->data; const uint8_t *buf_end = buf + avpkt->size; int video_size, video_type, i, j; video_size = AV_RL32(buf); video_type = buf[4]; buf += 5; if (video_size) { if (video_size < 0 || video_size > avpkt->size - 5) { av_log(avctx, AV_LOG_ERROR, "video size %d invalid\n", video_size); return AVERROR_INVALIDDATA; } if (avctx->reget_buffer(avctx, &s->frame) < 0) { av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return -1; } if (video_type == 0 || video_type == 1) { GetBitContext gb; init_get_bits(&gb, buf, 8 * video_size); for (j = 0; j < avctx->height; j += 8) for (i = 0; i < avctx->width; i += 8) decode8x8(&gb, s->frame.data[0] + j*s->frame.linesize[0] + i, s->frame.linesize[0], &s->dsp); buf += video_size; } else if (video_type == 2) { if (buf + 1 <= buf_end) { int v = *buf++; for (j = 0; j < avctx->height; j++) memset(s->frame.data[0] + j*s->frame.linesize[0], v, avctx->width); } } else { av_log(avctx, AV_LOG_WARNING, "unsupported frame type %i\n", video_type); return AVERROR_INVALIDDATA; } } if (buf_end - buf >= AVPALETTE_COUNT * 3) { for (i = 0; i < AVPALETTE_COUNT; i++) { uint32_t pal = AV_RB24(buf); s->palette[i] = 0xFF << 24 | pal << 2 | ((pal >> 4) & 0x30303); buf += 3; } s->palette_has_changed = 1; } if (video_size) { s->frame.key_frame = 1; s->frame.pict_type = AV_PICTURE_TYPE_I; s->frame.palette_has_changed = s->palette_has_changed; s->palette_has_changed = 0; memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE); *data_size = sizeof(AVFrame); *(AVFrame*)data = s->frame; } return avpkt->size; }