3 * Copyright (c) 2015 Rodger Combs
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
29 #include "libavutil/atomic.h"
30 #include "libavutil/avassert.h"
31 #include "libavutil/buffer.h"
32 #include "libavutil/common.h"
33 #include "libavutil/opt.h"
34 #include "libavutil/log.h"
37 #include <interface/mmal/mmal.h>
38 #include <interface/mmal/util/mmal_util.h>
39 #include <interface/mmal/util/mmal_util_params.h>
40 #include <interface/mmal/util/mmal_default_components.h>
42 typedef struct FFBufferEntry {
48 struct FFBufferEntry *next;
51 // MMAL_POOL_T destroys all of its MMAL_BUFFER_HEADER_Ts. If we want correct
52 // refcounting for AVFrames, we can free the MMAL_POOL_T only after all AVFrames
53 // have been unreferenced.
54 typedef struct FFPoolRef {
55 volatile int refcount;
59 typedef struct FFBufferRef {
60 MMAL_BUFFER_HEADER_T *buffer;
64 typedef struct MMALDecodeContext {
68 AVBitStreamFilterContext *bsfc;
70 MMAL_COMPONENT_T *decoder;
71 MMAL_QUEUE_T *queue_decoded_frames;
75 // Waiting input packets. Because the libavcodec API requires decoding and
76 // returning packets in lockstep, it can happen that queue_decoded_frames
77 // contains almost all surfaces - then the decoder input queue can quickly
78 // fill up and won't accept new input either. Without consuming input, the
79 // libavcodec API can't return new frames, and we have a logical deadlock.
80 // This is avoided by queuing such buffers here.
81 FFBufferEntry *waiting_buffers, *waiting_buffers_tail;
84 int64_t frames_output;
89 // Assume decoder is guaranteed to produce output after at least this many
90 // packets (where each packet contains 1 frame).
91 #define MAX_DELAYED_FRAMES 16
93 static void ffmmal_poolref_unref(FFPoolRef *ref)
95 if (ref && avpriv_atomic_int_add_and_fetch(&ref->refcount, -1) == 0) {
96 mmal_pool_destroy(ref->pool);
101 static void ffmmal_release_frame(void *opaque, uint8_t *data)
103 FFBufferRef *ref = (void *)data;
105 mmal_buffer_header_release(ref->buffer);
106 ffmmal_poolref_unref(ref->pool);
111 // Setup frame with a new reference to buffer. The buffer must have been
112 // allocated from the given pool.
113 static int ffmmal_set_ref(AVFrame *frame, FFPoolRef *pool,
114 MMAL_BUFFER_HEADER_T *buffer)
116 FFBufferRef *ref = av_mallocz(sizeof(*ref));
118 return AVERROR(ENOMEM);
121 ref->buffer = buffer;
123 frame->buf[0] = av_buffer_create((void *)ref, sizeof(*ref),
124 ffmmal_release_frame, NULL,
125 AV_BUFFER_FLAG_READONLY);
126 if (!frame->buf[0]) {
128 return AVERROR(ENOMEM);
131 avpriv_atomic_int_add_and_fetch(&ref->pool->refcount, 1);
132 mmal_buffer_header_acquire(buffer);
134 frame->format = AV_PIX_FMT_MMAL;
135 frame->data[3] = (uint8_t *)ref->buffer;
139 static void ffmmal_stop_decoder(AVCodecContext *avctx)
141 MMALDecodeContext *ctx = avctx->priv_data;
142 MMAL_COMPONENT_T *decoder = ctx->decoder;
143 MMAL_BUFFER_HEADER_T *buffer;
145 mmal_port_disable(decoder->input[0]);
146 mmal_port_disable(decoder->output[0]);
147 mmal_port_disable(decoder->control);
149 mmal_port_flush(decoder->input[0]);
150 mmal_port_flush(decoder->output[0]);
151 mmal_port_flush(decoder->control);
153 while ((buffer = mmal_queue_get(ctx->queue_decoded_frames)))
154 mmal_buffer_header_release(buffer);
156 while (ctx->waiting_buffers) {
157 FFBufferEntry *buffer = ctx->waiting_buffers;
159 ctx->waiting_buffers = buffer->next;
161 av_buffer_unref(&buffer->ref);
164 ctx->waiting_buffers_tail = NULL;
166 ctx->frames_output = ctx->eos_received = ctx->eos_sent = ctx->packets_sent = 0;
169 static av_cold int ffmmal_close_decoder(AVCodecContext *avctx)
171 MMALDecodeContext *ctx = avctx->priv_data;
174 ffmmal_stop_decoder(avctx);
176 mmal_component_destroy(ctx->decoder);
178 mmal_queue_destroy(ctx->queue_decoded_frames);
179 mmal_pool_destroy(ctx->pool_in);
180 ffmmal_poolref_unref(ctx->pool_out);
183 av_bitstream_filter_close(ctx->bsfc);
188 static void input_callback(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
191 AVBufferRef *buf = buffer->user_data;
192 av_buffer_unref(&buf);
194 mmal_buffer_header_release(buffer);
197 static void output_callback(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
199 AVCodecContext *avctx = (AVCodecContext*)port->userdata;
200 MMALDecodeContext *ctx = avctx->priv_data;
202 mmal_queue_put(ctx->queue_decoded_frames, buffer);
205 static void control_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
207 AVCodecContext *avctx = (AVCodecContext*)port->userdata;
208 MMAL_STATUS_T status;
210 if (buffer->cmd == MMAL_EVENT_ERROR) {
211 status = *(uint32_t *)buffer->data;
212 av_log(avctx, AV_LOG_ERROR, "MMAL error %d on control port\n", (int)status);
215 av_get_codec_tag_string(s, sizeof(s), buffer->cmd);
216 av_log(avctx, AV_LOG_WARNING, "Unknown MMAL event %s on control port\n", s);
219 mmal_buffer_header_release(buffer);
222 // Feed free output buffers to the decoder.
223 static int ffmmal_fill_output_port(AVCodecContext *avctx)
225 MMALDecodeContext *ctx = avctx->priv_data;
226 MMAL_BUFFER_HEADER_T *buffer;
227 MMAL_STATUS_T status;
230 return AVERROR_UNKNOWN; // format change code failed with OOM previously
232 while ((buffer = mmal_queue_get(ctx->pool_out->pool->queue))) {
233 if ((status = mmal_port_send_buffer(ctx->decoder->output[0], buffer))) {
234 mmal_buffer_header_release(buffer);
235 av_log(avctx, AV_LOG_ERROR, "MMAL error %d when sending output buffer.\n", (int)status);
236 return AVERROR_UNKNOWN;
243 static enum AVColorSpace ffmmal_csp_to_av_csp(MMAL_FOURCC_T fourcc)
246 case MMAL_COLOR_SPACE_BT470_2_BG:
247 case MMAL_COLOR_SPACE_BT470_2_M:
248 case MMAL_COLOR_SPACE_ITUR_BT601: return AVCOL_SPC_BT470BG;
249 case MMAL_COLOR_SPACE_ITUR_BT709: return AVCOL_SPC_BT709;
250 case MMAL_COLOR_SPACE_FCC: return AVCOL_SPC_FCC;
251 case MMAL_COLOR_SPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
252 default: return AVCOL_SPC_UNSPECIFIED;
256 static int ffmal_update_format(AVCodecContext *avctx)
258 MMALDecodeContext *ctx = avctx->priv_data;
259 MMAL_STATUS_T status;
261 MMAL_COMPONENT_T *decoder = ctx->decoder;
262 MMAL_ES_FORMAT_T *format_out = decoder->output[0]->format;
264 ffmmal_poolref_unref(ctx->pool_out);
265 if (!(ctx->pool_out = av_mallocz(sizeof(*ctx->pool_out)))) {
266 ret = AVERROR(ENOMEM);
269 ctx->pool_out->refcount = 1;
274 if ((status = mmal_port_parameter_set_uint32(decoder->output[0], MMAL_PARAMETER_EXTRA_BUFFERS, ctx->extra_buffers)))
277 if (avctx->pix_fmt == AV_PIX_FMT_MMAL) {
278 format_out->encoding = MMAL_ENCODING_OPAQUE;
280 format_out->encoding_variant = format_out->encoding = MMAL_ENCODING_I420;
283 if ((status = mmal_port_format_commit(decoder->output[0])))
286 if ((ret = ff_set_dimensions(avctx, format_out->es->video.crop.x + format_out->es->video.crop.width,
287 format_out->es->video.crop.y + format_out->es->video.crop.height)) < 0)
290 if (format_out->es->video.par.num && format_out->es->video.par.den) {
291 avctx->sample_aspect_ratio.num = format_out->es->video.par.num;
292 avctx->sample_aspect_ratio.den = format_out->es->video.par.den;
295 avctx->colorspace = ffmmal_csp_to_av_csp(format_out->es->video.color_space);
297 decoder->output[0]->buffer_size =
298 FFMAX(decoder->output[0]->buffer_size_min, decoder->output[0]->buffer_size_recommended);
299 decoder->output[0]->buffer_num =
300 FFMAX(decoder->output[0]->buffer_num_min, decoder->output[0]->buffer_num_recommended) + ctx->extra_buffers;
301 ctx->pool_out->pool = mmal_pool_create(decoder->output[0]->buffer_num,
302 decoder->output[0]->buffer_size);
303 if (!ctx->pool_out->pool) {
304 ret = AVERROR(ENOMEM);
311 return ret < 0 ? ret : AVERROR_UNKNOWN;
314 static av_cold int ffmmal_init_decoder(AVCodecContext *avctx)
316 MMALDecodeContext *ctx = avctx->priv_data;
317 MMAL_STATUS_T status;
318 MMAL_ES_FORMAT_T *format_in;
319 MMAL_COMPONENT_T *decoder;
324 if ((ret = ff_get_format(avctx, avctx->codec->pix_fmts)) < 0)
327 avctx->pix_fmt = ret;
329 if ((status = mmal_component_create(MMAL_COMPONENT_DEFAULT_VIDEO_DECODER, &ctx->decoder)))
332 decoder = ctx->decoder;
334 format_in = decoder->input[0]->format;
335 format_in->type = MMAL_ES_TYPE_VIDEO;
336 format_in->encoding = MMAL_ENCODING_H264;
337 format_in->es->video.width = FFALIGN(avctx->width, 32);
338 format_in->es->video.height = FFALIGN(avctx->height, 16);
339 format_in->es->video.crop.width = avctx->width;
340 format_in->es->video.crop.height = avctx->height;
341 format_in->es->video.frame_rate.num = 24000;
342 format_in->es->video.frame_rate.den = 1001;
343 format_in->es->video.par.num = avctx->sample_aspect_ratio.num;
344 format_in->es->video.par.den = avctx->sample_aspect_ratio.den;
345 format_in->flags = MMAL_ES_FORMAT_FLAG_FRAMED;
347 if (avctx->codec->id == AV_CODEC_ID_H264 && avctx->extradata && avctx->extradata[0] == 1) {
350 ctx->bsfc = av_bitstream_filter_init("h264_mp4toannexb");
352 av_log(avctx, AV_LOG_ERROR, "Cannot open the h264_mp4toannexb BSF!\n");
353 ret = AVERROR(ENOSYS);
356 av_bitstream_filter_filter(ctx->bsfc, avctx, NULL, &dummy_p, &dummy_int, NULL, 0, 0);
359 if (avctx->extradata_size) {
360 if ((status = mmal_format_extradata_alloc(format_in, avctx->extradata_size)))
362 format_in->extradata_size = avctx->extradata_size;
363 memcpy(format_in->extradata, avctx->extradata, format_in->extradata_size);
366 if ((status = mmal_port_format_commit(decoder->input[0])))
369 decoder->input[0]->buffer_num =
370 FFMAX(decoder->input[0]->buffer_num_min, 20);
371 decoder->input[0]->buffer_size =
372 FFMAX(decoder->input[0]->buffer_size_min, 512 * 1024);
373 ctx->pool_in = mmal_pool_create(decoder->input[0]->buffer_num, 0);
375 ret = AVERROR(ENOMEM);
379 if ((ret = ffmal_update_format(avctx)) < 0)
382 ctx->queue_decoded_frames = mmal_queue_create();
383 if (!ctx->queue_decoded_frames)
386 decoder->input[0]->userdata = (void*)avctx;
387 decoder->output[0]->userdata = (void*)avctx;
388 decoder->control->userdata = (void*)avctx;
390 if ((status = mmal_port_enable(decoder->control, control_port_cb)))
392 if ((status = mmal_port_enable(decoder->input[0], input_callback)))
394 if ((status = mmal_port_enable(decoder->output[0], output_callback)))
397 if ((status = mmal_component_enable(decoder)))
403 ffmmal_close_decoder(avctx);
404 return ret < 0 ? ret : AVERROR_UNKNOWN;
407 static void ffmmal_flush(AVCodecContext *avctx)
409 MMALDecodeContext *ctx = avctx->priv_data;
410 MMAL_COMPONENT_T *decoder = ctx->decoder;
411 MMAL_STATUS_T status;
413 ffmmal_stop_decoder(avctx);
415 if ((status = mmal_port_enable(decoder->control, control_port_cb)))
417 if ((status = mmal_port_enable(decoder->input[0], input_callback)))
419 if ((status = mmal_port_enable(decoder->output[0], output_callback)))
425 av_log(avctx, AV_LOG_ERROR, "MMAL flush error: %i\n", (int)status);
428 // Split packets and add them to the waiting_buffers list. We don't queue them
429 // immediately, because it can happen that the decoder is temporarily blocked
430 // (due to us not reading/returning enough output buffers) and won't accept
431 // new input. (This wouldn't be an issue if MMAL input buffers always were
432 // complete frames - then the input buffer just would have to be big enough.)
433 static int ffmmal_add_packet(AVCodecContext *avctx, AVPacket *avpkt)
435 MMALDecodeContext *ctx = avctx->priv_data;
436 AVBufferRef *buf = NULL;
438 uint8_t *data = (uint8_t *)"";
448 if ((ret = av_bitstream_filter_filter(ctx->bsfc, avctx, NULL,
449 &tmp_data, &tmp_size,
450 avpkt->data, avpkt->size,
451 avpkt->flags & AV_PKT_FLAG_KEY)) < 0)
453 buf = av_buffer_create(tmp_data, tmp_size, NULL, NULL, 0);
456 buf = av_buffer_ref(avpkt->buf);
458 buf = av_buffer_alloc(avpkt->size);
460 memcpy(buf->data, avpkt->data, avpkt->size);
464 ret = AVERROR(ENOMEM);
474 FFBufferEntry *buffer = av_mallocz(sizeof(*buffer));
476 ret = AVERROR(ENOMEM);
481 buffer->length = FFMIN(size, ctx->decoder->input[0]->buffer_size);
484 buffer->flags |= MMAL_BUFFER_HEADER_FLAG_FRAME_START;
486 data += buffer->length;
487 size -= buffer->length;
489 buffer->pts = avpkt->pts == AV_NOPTS_VALUE ? MMAL_TIME_UNKNOWN : avpkt->pts;
490 buffer->dts = avpkt->dts == AV_NOPTS_VALUE ? MMAL_TIME_UNKNOWN : avpkt->dts;
493 buffer->flags |= MMAL_BUFFER_HEADER_FLAG_FRAME_END;
495 if (!buffer->length) {
496 buffer->flags |= MMAL_BUFFER_HEADER_FLAG_EOS;
501 buffer->ref = av_buffer_ref(buf);
504 ret = AVERROR(ENOMEM);
509 // Insert at end of the list
510 if (!ctx->waiting_buffers)
511 ctx->waiting_buffers = buffer;
512 if (ctx->waiting_buffers_tail)
513 ctx->waiting_buffers_tail->next = buffer;
514 ctx->waiting_buffers_tail = buffer;
518 av_buffer_unref(&buf);
522 // Move prepared/split packets from waiting_buffers to the MMAL decoder.
523 static int ffmmal_fill_input_port(AVCodecContext *avctx)
525 MMALDecodeContext *ctx = avctx->priv_data;
527 while (ctx->waiting_buffers) {
528 MMAL_BUFFER_HEADER_T *mbuffer;
529 FFBufferEntry *buffer;
530 MMAL_STATUS_T status;
532 mbuffer = mmal_queue_get(ctx->pool_in->queue);
536 buffer = ctx->waiting_buffers;
538 mmal_buffer_header_reset(mbuffer);
540 mbuffer->pts = buffer->pts;
541 mbuffer->dts = buffer->dts;
542 mbuffer->flags = buffer->flags;
543 mbuffer->data = buffer->data;
544 mbuffer->length = buffer->length;
545 mbuffer->user_data = buffer->ref;
546 mbuffer->alloc_size = ctx->decoder->input[0]->buffer_size;
548 if ((status = mmal_port_send_buffer(ctx->decoder->input[0], mbuffer))) {
549 mmal_buffer_header_release(mbuffer);
550 av_buffer_unref(&buffer->ref);
553 // Remove from start of the list
554 ctx->waiting_buffers = buffer->next;
555 if (ctx->waiting_buffers_tail == buffer)
556 ctx->waiting_buffers_tail = NULL;
560 av_log(avctx, AV_LOG_ERROR, "MMAL error %d when sending input\n", (int)status);
561 return AVERROR_UNKNOWN;
568 static int ffmal_copy_frame(AVCodecContext *avctx, AVFrame *frame,
569 MMAL_BUFFER_HEADER_T *buffer)
571 MMALDecodeContext *ctx = avctx->priv_data;
574 if (avctx->pix_fmt == AV_PIX_FMT_MMAL) {
576 return AVERROR_UNKNOWN; // format change code failed with OOM previously
578 if ((ret = ff_decode_frame_props(avctx, frame)) < 0)
581 if ((ret = ffmmal_set_ref(frame, ctx->pool_out, buffer)) < 0)
584 int w = FFALIGN(avctx->width, 32);
585 int h = FFALIGN(avctx->height, 16);
590 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
593 ptr = buffer->data + buffer->type->video.offset[0];
594 for (i = 0; i < avctx->height; i++)
595 memcpy(frame->data[0] + frame->linesize[0] * i, ptr + w * i, avctx->width);
599 for (plane = 1; plane < 3; plane++) {
600 for (i = 0; i < avctx->height / 2; i++)
601 memcpy(frame->data[plane] + frame->linesize[plane] * i, ptr + w / 2 * i, (avctx->width + 1) / 2);
602 ptr += w / 2 * h / 2;
606 if (buffer->pts != MMAL_TIME_UNKNOWN) {
607 frame->pkt_pts = buffer->pts;
608 frame->pts = buffer->pts;
615 // Fetch a decoded buffer and place it into the frame parameter.
616 static int ffmmal_read_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame)
618 MMALDecodeContext *ctx = avctx->priv_data;
619 MMAL_BUFFER_HEADER_T *buffer = NULL;
620 MMAL_STATUS_T status = 0;
623 if (ctx->eos_received)
627 // To ensure decoding in lockstep with a constant delay between fed packets
628 // and output frames, we always wait until an output buffer is available.
629 // Except during start we don't know after how many input packets the decoder
630 // is going to return the first buffer, and we can't distinguish decoder
631 // being busy from decoder waiting for input. So just poll at the start and
632 // keep feeding new data to the buffer.
633 // We are pretty sure the decoder will produce output if we sent more input
634 // frames than what a h264 decoder could logically delay. This avoids too
635 // excessive buffering.
636 // We also wait if we sent eos, but didn't receive it yet (think of decoding
637 // stream with a very low number of frames).
638 if (ctx->frames_output || ctx->packets_sent > MAX_DELAYED_FRAMES || ctx->eos_sent) {
639 buffer = mmal_queue_wait(ctx->queue_decoded_frames);
641 buffer = mmal_queue_get(ctx->queue_decoded_frames);
646 ctx->eos_received |= !!(buffer->flags & MMAL_BUFFER_HEADER_FLAG_EOS);
647 if (ctx->eos_received)
650 if (buffer->cmd == MMAL_EVENT_FORMAT_CHANGED) {
651 MMAL_COMPONENT_T *decoder = ctx->decoder;
652 MMAL_EVENT_FORMAT_CHANGED_T *ev = mmal_event_format_changed_get(buffer);
653 MMAL_BUFFER_HEADER_T *stale_buffer;
655 av_log(avctx, AV_LOG_INFO, "Changing output format.\n");
657 if ((status = mmal_port_disable(decoder->output[0])))
660 while ((stale_buffer = mmal_queue_get(ctx->queue_decoded_frames)))
661 mmal_buffer_header_release(stale_buffer);
663 mmal_format_copy(decoder->output[0]->format, ev->format);
665 if ((ret = ffmal_update_format(avctx)) < 0)
668 if ((status = mmal_port_enable(decoder->output[0], output_callback)))
671 if ((ret = ffmmal_fill_output_port(avctx)) < 0)
674 if ((ret = ffmmal_fill_input_port(avctx)) < 0)
677 mmal_buffer_header_release(buffer);
679 } else if (buffer->cmd) {
681 av_get_codec_tag_string(s, sizeof(s), buffer->cmd);
682 av_log(avctx, AV_LOG_WARNING, "Unknown MMAL event %s on output port\n", s);
684 } else if (buffer->length == 0) {
685 // Unused output buffer that got drained after format change.
686 mmal_buffer_header_release(buffer);
690 ctx->frames_output++;
692 if ((ret = ffmal_copy_frame(avctx, frame, buffer)) < 0)
701 mmal_buffer_header_release(buffer);
702 if (status && ret >= 0)
703 ret = AVERROR_UNKNOWN;
707 static int ffmmal_decode(AVCodecContext *avctx, void *data, int *got_frame,
710 AVFrame *frame = data;
713 if ((ret = ffmmal_add_packet(avctx, avpkt)) < 0)
716 if ((ret = ffmmal_fill_input_port(avctx)) < 0)
719 if ((ret = ffmmal_fill_output_port(avctx)) < 0)
722 if ((ret = ffmmal_read_frame(avctx, frame, got_frame)) < 0)
725 // ffmmal_read_frame() can block for a while. Since the decoder is
726 // asynchronous, it's a good idea to fill the ports again.
728 if ((ret = ffmmal_fill_output_port(avctx)) < 0)
731 if ((ret = ffmmal_fill_input_port(avctx)) < 0)
737 AVHWAccel ff_h264_mmal_hwaccel = {
739 .type = AVMEDIA_TYPE_VIDEO,
740 .id = AV_CODEC_ID_H264,
741 .pix_fmt = AV_PIX_FMT_MMAL,
744 static const AVOption options[]={
745 {"extra_buffers", "extra buffers", offsetof(MMALDecodeContext, extra_buffers), AV_OPT_TYPE_INT, {.i64 = 10}, 0, 256, 0},
749 static const AVClass ffmmaldec_class = {
750 .class_name = "mmaldec",
752 .version = LIBAVUTIL_VERSION_INT,
755 AVCodec ff_h264_mmal_decoder = {
757 .long_name = NULL_IF_CONFIG_SMALL("h264 (mmal)"),
758 .type = AVMEDIA_TYPE_VIDEO,
759 .id = AV_CODEC_ID_H264,
760 .priv_data_size = sizeof(MMALDecodeContext),
761 .init = ffmmal_init_decoder,
762 .close = ffmmal_close_decoder,
763 .decode = ffmmal_decode,
764 .flush = ffmmal_flush,
765 .priv_class = &ffmmaldec_class,
766 .capabilities = CODEC_CAP_DELAY,
767 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_MMAL,